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  • Spotlight Summary by Bernhard Schmauss

    • Coherent pulse interrogation system for fiber Bragg grating sensing of strain and pressure in dynamic extremes of materials
    • Optical fiber sensors for measurements in difficult environments have been intensively studied for many years. Some of their most important advantages are high sensitivity, immunity to electromagnetic interference and...
    • Opt. Express 23(11) 14219-14233 (2015) View: Abstract | HTML | PDF

Information Acquisition, Processing, and Display

  • Spotlight Summary by Jean-Baptiste Masson

    • Generation of arbitrary order Bessel beams via 3D printed axicons at the terahertz frequency range
    • The growing field of terahertz (THz) optics poses important challenges: the unusual interaction of THz radiation with usual optical materials, and the constraints on optical design imposed by the very large wavelengths...
    • Appl. Opt. 54(36) 10641-10649 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Gianluca Galzerano

    • Sub-Doppler resolution mid-infrared spectroscopy using a difference-frequency-generation source spectrally narrowed by laser linewidth transfer
    • The continuous progress in the fields of high-resolution spectroscopy and frequency metrology is strongly correlated with the availability of highly coherent light sources with narrow emission linewidth and broad...
    • Opt. Lett. 40(23) 5467-5470 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Avner Fleischer

    • Combined high-harmonic interferometries for vectorial spectroscopy
    • How to characterize the polarization of extreme-ultraviolet (XUV) high-harmonic radiation without an XUV polarizer? This question is important for two reasons. First, XUV polarizers are very lossy and bandwidth-limited....
    • Opt. Lett. 40(22) 5387-5390 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Roarke Horstmeyer

    • Spectral edge: gradient-preserving spectral mapping for image fusion
    • A huge variety of cameras can now capture information beyond what our eyes can “see”. This information includes wavelengths in the ultraviolet or infrared, or segments of the color rainbow that are incredibly fine and...
    • J. Opt. Soc. Am. A 32(12) 2384-2396 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Francesco D'Amato

    • Development of a compact multipass oxygen sensor used for gas diffusion studies in opaque media
    • Any physical measurement requires a probe. This probe must be tailored in order to avoid as much as possible any perturbation, both to the quantity to be determined, and to the experimental setup. When the measurement...
    • Appl. Opt. 54(33) 9772-9778 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Lei Tian

    • Three-dimensional quantitative phase imaging via tomographic deconvolution phase microscopy
    • Imaging the 3D internal structure of an object is a fundamental problem. 3D quantitative phase imaging (QPI) is a non-invasive technique that measures the refractive index distribution without staining or labeling. In...
    • Appl. Opt. 54(31) 9213-9227 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Alexander Baev

    • Raman optical activity spectroscopy by visible-excited coherent anti-Stokes Raman scattering
    • Raman Optical Activity (ROA) spectroscopy is an essential analytical tool that has proved indispensable in, among other fields, biochemistry, where the majority of the studied objects are chiral molecules. However, the...
    • Opt. Lett. 40(17) 4170-4173 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Bodo Wilts

    • Quantitative reflectance spectra of solid powders as a function of particle size
    • Light-matter interaction is a very complicated process. In particular reflectance, the amount of light reflected away from a material surface, is difficult to describe quantitatively since it depends on the complex...
    • Appl. Opt. 54(15) 4863-4875 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Kedar Khare

    • Inline digital holographic movie based on a double-sideband filter
    • Digital holography has become an important modality for fast and accurate quantitative phase imaging applications relevant to biomedical diagnostics, optical metrology, displays, etc. There are two important classes of...
    • Opt. Lett. 40(17) 4142-4145 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Miro Erkintalo

    • Yb:fiber laser-based, spectrally coherent and efficient generation of femtosecond 1.3-μm pulses from a fiber with two zero-dispersion wavelengths
    • Many applications require laser light with a specific wavelength, and this has prompted decades of research into developing materials that lase at new regions of the electromagnetic spectrum. But despite great efforts,...
    • Opt. Lett. 40(15) 3631-3634 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Bernhard Schmauss

    • Two-fold transmission reach enhancement enabled by transmitter-side digital backpropagation and optical frequency comb-derived information carriers
    • Today, optical fiber telecommunication systems are based on high-order modulation formats, coherent detection schemes, digital signal processing and channel coding techniques to fulfill the ever increasing demands for...
    • Opt. Express 23(16) 20774-20783 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Brad Deutsch

    • Lycurgus Cup: inverse problem using photographs for characterization of matter
    • The Lycurgus Cup was made in 4th-century Rome, and has dichroic properties: its color depends on the direction of illumination. Lit in reflection, the glass looks green, while in transmission it ranges from purple to...
    • J. Opt. Soc. Am. A 32(8) 1544-1555 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Anne Hirsikko

    • Transparent material thickness measurements by Raman scattering
    • Much of the Polar region is covered by ice. Properties (such as areal coverage, thickness, optical properties and salinity) of ice are important indicators of interactions between ice and its surroundings, and thus,...
    • Appl. Opt. 54(19) 5943-5948 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Arel Weisberg

    • Determination of carcinogenic fluorine in cigarettes using pulsed UV laser-induced breakdown spectroscopy
    • Beyond adding to the growing literature on LIBS (laser induced breakdown spectroscopy) applications, this Applied Optics paper should inspire researchers to utilize LIBS in their fields of study. This is because the...
    • Appl. Opt. 54(17) 5560-5567 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Richard Bowman

    • Optical trap for both transparent and absorbing particles in air using a single shaped laser beam
    • When light hits an airborne particle, it can impart both energy and momentum. Each of these physical mechanisms can cause the particle to move; energy absorbed by a particle can heat up one side of it, which in turn...
    • Opt. Lett. 40(12) 2798-2801 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Brynmor Davis

    • Finite sampling corrected 3D noise with confidence intervals
    • Imaging devices are subject to degradation by noise from a variety of sources. Differing physical origins result in differing spatio-temporal characteristics of the noise terms that combine to degrade a video stream. ...
    • Appl. Opt. 54(15) 4907-4915 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Martin Hieronymi

    • Polarized reflectance and transmittance properties of windblown sea surfaces
    • The polarization of light is finding its way into the awareness of the ocean optics community, and this Applied Optics article is a great contribution in this direction – this is really applied optics!

      The...
    • Appl. Opt. 54(15) 4828-4849 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by David M. Paganin

    • Microgenetic optimization algorithm for optimal wavefront shaping
    • Optics has so much to draw from the natural world, on a number of levels. We have of course the natural optical systems that range so broadly, from diffraction gratings to nano-optical systems, from mirages to the...
    • Appl. Opt. 54(6) 1485-1491 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Anders Tegtmeier Pedersen

    • High-efficiency receiver architecture for resonance-fluorescence and Doppler lidars
    • The mesosphere and lower thermosphere are parts of the middle atmosphere stretching from around 50 km to well beyond 100 km above the ground. Whilst receiving modest attention in an everyday context, these cold and...
    • Appl. Opt. 54(11) 3173-3184 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Anne Hirsikko

    • Retrieval of temperature from a multiple-channel Rayleigh-scatter lidar using an optimal estimation method
    • Temperature is one of the fundamental variables describing the state of the atmosphere, and the ability to observe temperature changes reliably is essential for applications ranging from climate research to weather...
    • Appl. Opt. 54(8) 1872-1889 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Richard Bowman

    • Digital holography super-resolution for accurate three-dimensional reconstruction of particle holograms
    • In-line digital holography is fast becoming a widespread method for imaging and tracking micro-objects in three dimensions. Employing a simple bright-field microscope and adding transmission illumination from a...
    • Opt. Lett. 40(2) 217-220 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Jonathan J. Makela

    • Advanced mesospheric temperature mapper for high-latitude airglow studies
    • The Earth’s mesosphere and lower thermosphere, the region of the atmosphere near 100-km altitude, represent the boundary between our world and space. The mesosphere is the coldest region of the atmosphere, with...
    • Appl. Opt. 53(26) 5934-5943 (2014) View: Abstract | HTML | PDF

  • Spotlight Summary by Andrea Reale e Alessio Gagliardi

    • Low-power communication with a photonic heat pump
    • A LED can work as a thermodynamic heat pump: under certain conditions, it can use externally supplied electrical work to pump heat from its own semiconductor lattice to the light it emits. This process manifests itself...
    • Opt. Express 22(S7) A1650-A1658 (2014) View: Abstract | HTML | PDF

Light–Matter Interactions

  • Spotlight Summary by Andrey N. Kuzmin

    • An 11.5 W Yb:YAG planar waveguide laser fabricated via pulsed laser deposition
    • High power Yb:YAG thin film laser materials fabricated by laser deposition are now available. Researchers at the University of Southampton demonstrated multi-watt laser action from a 15 μm-thick planar waveguide...
    • Opt. Mater. Express 6(1) 91-96 (2016) View: Abstract | HTML | PDF

  • Spotlight Summary by Taek Yong Hwang

    • 140-fs duration and 60-W peak power blue-violet optical pulses generated by a dispersion-compensated GaInN mode-locked semiconductor laser diode using a nonlinear pulse compressor
    • According to the uncertainty relation, the product of a pulse’s temporal width and that of its frequency spectrum is fundamentally required to be larger than a certain numerical constant, meaning that the generation of...
    • Opt. Express 23(25) 31766-31771 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Andrew Sarangan

    • In situ probing of mode-locked vertical-external-cavity-surface-emitting lasers
    • Can one probe a laser cavity to examine its sub-picosecond gain dynamics? This paper demonstrates a technique for doing exactly that using a femtosecond fiber laser as the probe. The large gain bandwidth of...
    • Opt. Lett. 40(23) 5459-5462 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by László Pálfalvi

    • Scanning nonlinear absorption in lithium niobate over the time regime of small polaron formation
    • Since the 90’s the z-scan method is a standard procedure for the characterization of nonlinear material properties. Originally the technique was developed for the determination of the nonlinear absorption and refraction...
    • Opt. Mater. Express 5(12) 2729-2741 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Paul Steinvurzel

    • Optical side scattering radiometry for high resolution, wide dynamic range longitudinal assessment of optical fibers
    • An old technique has been adapted to achieve unprecedented dynamic range and spatial resolution in measuring transmission loss of km-length photonic bandgap fibers. In side scatter radiometry, one end of an optical...
    • Opt. Express 23(21) 27960-27974 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Brad Deutsch

    • Large-area fabrication of TiN nanoantenna arrays for refractory plasmonics in the mid-infrared by femtosecond direct laser writing and interference lithography [Invited]
    • Optical antennas might be used to efficiently harvest solar energy, if we can manage to fabricate them. Just like radio antennas do with radio waves, optical antennas convert propagating radiation (visible or infrared...
    • Opt. Mater. Express 5(11) 2625-2633 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Michael Frosz

    • Octave-spanning coherent supercontinuum generation in a silicon nitride waveguide
    • The supercontinuum reported in this work is not only spectrally coherent and spans more than one octave: it is also generated in a compact chip. The chip consists of a silicon nitride waveguide...
    • Opt. Lett. 40(21) 5117-5120 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Anton K. Vershovskii

    • Highly stable atomic vector magnetometer based on free spin precession
    • The most basic principle upon which quantum magnetometers rely is measuring the frequency of the Larmor precession – the precession of magnetic moment of the atom around a magnetic field. This frequency depends on the...
    • Opt. Express 23(17) 22108-22115 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Göery Genty

    • Writing and erasing of temporal cavity solitons by direct phase modulation of the cavity driving field
    • Optical solitons are peculiar objects that have the remarkable property of retaining their shape when propagating in a nonlinear dispersive medium. In the time domain, solitons manifest themselves as a result of perfect...
    • Opt. Lett. 40(20) 4755-4758 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Filippo Miatto

    • Two-mode squeezed states as Schrödinger cat-like states
    • When Erwin Schrödinger concocted his gedankenexperiment, he managed to phrase a very deep problem in quantum mechanics in terms that everyone could understand. However, the metaphor that he used is too extreme to be...
    • J. Opt. Soc. Am. B 32(10) 2190-2197 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Taek Yong Hwang

    • High-energy large-aperture Ti:sapphire amplifier for 5 PW laser pulses
    • Ultrafast lasers have contributed to expanding continuously our understanding of light-matter interactions with an increase in their peak power. Historically, to generate ultrafast laser pulses with a higher peak power,...
    • Opt. Lett. 40(21) 5011-5014 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Cristian Manzoni

    • Few-cycle near-infrared pulses from a degenerate 1 GHz optical parametric oscillator
    • One of the most fascinating topics in modern astronomy is the search for exoplanets, i.e. those planets that orbit a star other than the Sun. How is this research connected to laser technology? And to this paper in...
    • Opt. Lett. 40(17) 4102-4105 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Francesco Morichetti

    • Broadband mid-infrared frequency comb generation in a Si3N4 microresonator
    • No more than four years ago, a broadband integrated frequency comb generator operating in the near-infrared range was highlighted in Spotlight on Optics. (
    • Opt. Lett. 40(21) 4823-4826 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Nickolas Vamivakas

    • Ultra hybrid plasmonics: strong coupling of plexcitons with plasmon polaritons
    • The understanding and control of light-matter interaction has not only provided new insight into classical and quantum optical phenomena, but also has led to a myriad of exotic optoelectronic devices. Significant...
    • Opt. Lett. 40(14) 3424-3427 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Yaroslav V. Kartashov

    • Observation of stable-vector vortex solitons
    • The exploration of new nonlinear materials and geometries where stable self-sustained excitations in the form of vortex solitons can exist is one of the most attractive routes in modern nonlinear photonics. The authors...
    • Opt. Lett. 40(17) 4182-4185 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Apratim Majumder and Rajesh Menon

    • Gold triple-helix mid-infrared metamaterial by STED-inspired laser lithography
    • Overcoming the far-field diffraction limit using Stimulated Emission Depletion (STED) microscopy enabled the effective focusing of light to deep subwavelength dimensions, resulting in unprecedented resolution in all 3...
    • Opt. Lett. 40(17) 3986-3989 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Uwe Brauch

    • Two-dimensional pseudo-random optical phased array based on tandem optical injection locking of vertical cavity surface emitting lasers
    • The coherent superposition of laser beams – at least in principle – can solve two major challenges in one go:

      1. the scaling of the output power while conserving diffraction-limited beam quality, and...
    • Opt. Express 23(15) 19405-19416 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Juejun Hu

    • Silicon hybrid plasmonic microring resonator for sensing applications
    • Recent advances in integrated photonics technologies have enabled miniaturized on-chip optical devices to be used as sensitive chemical and biological molecular sensors. In particular, optical resonators offer a...
    • Appl. Opt. 54(23) 7131-7134 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Richard Bowman

    • Ultrastable measurement platform: sub-nm drift over hours in 3D at room temperature
    • Instrument drift is the bane of experimental science; the more sensitive the instrument, the more important it becomes to stop the sample moving. Even the tiniest influence of air currents or temperature instabilities...
    • Opt. Express 23(13) 16554-16564 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Patricia Segonds

    • Enhanced Kerr electro-optic nonlinearity and its application in controlling second-harmonic generation
    • In non-centrosymmetric crystals, third order nonlinear processes are hidden by second order ones. However, third order nonlinearities can be enhanced through the use of cascading, which opens the door to their...
    • Photon. Res. 3(4) 168-172 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Curtis Broadbent

    • Preservation of transverse spatial coherence in the storage of double light pulses
    • Quantum technologies hold the promise of paradigm-shifting increases in computational power and communication security. However, challenges arising from loss and decoherence make it difficult to achieve the stringent...
    • J. Opt. Soc. Am. B 32(7) 1318-1322 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Filippo Miatto

    • Bounds to precision for quantum interferometry with Gaussian states and operations
    • On the ultimate phase sensitivity: when less is more.

      Using one’s resources in the most efficient way possible is desirable for several reasons: we save time, we save efforts, we...
    • J. Opt. Soc. Am. B 32(7) 1354-1359 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by David R. Busch

    • Fast silicon photomultiplier improves signal harvesting and reduces complexity in time-domain diffuse optics
    • Diffuse optical measurements of tissue inform clinicians of deep tissue hemodynamics continuously, without ionizing radiation or invasive proves. The most ubiquitous of these systems is the pulse-oximeter, which...
    • Opt. Express 23(11) 13937-13946 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Katia Gallo

    • Tunable optical nonlinearity of silicon nanoparticles in solid state organic matrix
    • Fine structuring of optical materials is a powerful tool to shape their optical response, to control the way in which light impinging on them is reflected, scattered or transmitted. Scientists and engineers have been...
    • Opt. Mater. Express 5(7) 1606-1612 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Steffen Hädrich

    • High average power coherent vuv generation at 10 MHz repetition frequency by intracavity high harmonic generation
    • Sources of short wavelength radiation are becoming increasingly important for studies of the so-called nano-cosmos that has implications in driving fields such as physics, chemistry, biology, materials science or...
    • Opt. Express 23(12) 15107-15118 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Francesco Morichetti

    • Second-harmonic generation of light at 245 nm in a lithium tetraborate whispering gallery resonator
    • Switching the light on at any wavelength, easily and efficiently, is not an easy game. This is indeed one of the main issues people working in optics have to face, because a general-purpose recipe to build light sources...
    • Opt. Lett. 40(9) 1932-1935 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Enrique Gálvez

    • Shot-by-shot imaging of Hong–Ou–Mandel interference with an intensified sCMOS camera
    • Quantum phenomena baffle us through counter-intuitive predictions that are consistently verified. In a landmark experiment of quantum optics performed by L. Mandel and coworkers C.K. Hong and Z.Y. Ou, also known as the...
    • Opt. Lett. 40(7) 1540-1543 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Jean-Baptiste Masson

    • Cavity-enhanced optical Hall effect in two-dimensional free charge carrier gases detected at terahertz frequencies
    • The Optical Hall Effect (OHE) is the birefringence induced by the interaction of incident electromagnetic radiation with the free carriers in a material under a magnetic field. One of the uses of the OHE is the probing...
    • Opt. Lett. 40(12) 2688-2691 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Rudolf Saathof

    • Nanometer level characterization of the James Webb Space Telescope optomechanical systems using high-speed interferometry
    • Due to the perpetual pursuit to understand the origin of the universe, telescopes have continued to grow over the centuries in order to collect more light. Large telescopes make faint objects look brighter and otherwise...
    • Appl. Opt. 54(13) 4285-4298 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Marco Anni

    • Spatially variant color light source using amplified spontaneous emission from organic thin films
    • In a period in which the diffusion of Light Emitting Diodes (LEDs) for lighting applications is strongly increasing, the search for the next generation of broad-band light sources is already underway. According to many...
    • Opt. Mater. Express 5(3) 497-502 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Taek Yong Hwang

    • Full vector-field control of ultrashort laser pulses utilizing a single dual-layer spatial light modulator in a common-path setup
    • Spotlight on optics: The manipulation of the temporal shape of optical pulses has been extensively studied for a few decades, due to its importance in many practical applications including optical communications,...
    • J. Opt. Soc. Am. B 32(5) 933-945 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Taek Yong Hwang

    • Modeling and experiments of self-reflectivity under femtosecond ablation conditions
    • Femtosecond (fs) laser material processing has attracted a great deal of attention due to unique advantages over conventional laser processing techniques that employ nanosecond and longer pulsed lasers. One of the most...
    • J. Opt. Soc. Am. B 32(4) 606-616 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Georgi T. Georgiev

    • Establishment and application of the 0/45 reflectance factor scale over the shortwave infrared
    • The Bidirectional Reflectance Distribution Function (BRDF) is a fundamental quantity describing the reflectance properties of a target as a function of illumination and viewing geometries. However, there are only a few...
    • Appl. Opt. 54(10) 3064-3071 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Andrey N. Kuzmin

    • Shape-memory polymers as flexible resonator substrates for continuously tunable organic DFB lasers
    • Simple, robust and inexpensive tunable single-mode microlasers are of particular interest for a wide spectrum of commercial and scientific applications in the most challenging areas - health care, security and...
    • Opt. Mater. Express 5(3) 576-584 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Paul Steinvurzel

    • Passive coherent combining of CEP-stable few-cycle pulses from a temporally divided hollow fiber compressor
    • Lasers have been an integral part of the researcher’s toolkit for more than half a century now, and no matter how much optical power they deliver, there is always a drive for more. Laser systems are themselves...
    • Opt. Lett. 40(5) 709-712 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Ilya Shadrivov

    • Region specific enhancement of quantum dot emission using interleaved two-dimensional photonic crystals
    • The last decade has seen light sources becoming more efficient and more easily controllable following the advances in LED technology. A research team from the United States has proposed a practical approach to utilize...
    • Appl. Opt. 54(9) 2302-2308 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Thomas Udem

    • Direct 15-GHz mode-spacing optical frequency comb with a Kerr-lens mode-locked Yb:Y2O3 ceramic laser
    • Mode-locked lasers that emit ultrashort pulses with a very large repetition rate are highly desirable for certain frequency comb applications. The team of Yohei Kobayashi at the University of Tokyo has now been able to...
    • Opt. Express 23(2) 1276-1282 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Jean-Baptiste Masson

    • Nonclassical correlations between terahertz-bandwidth photons mediated by rotational quanta in hydrogen molecules
    • The development of information technology relying on quantum physical properties is attracting more and more interest with the goal of everyday technologies relying on quantum computation principles. Photonics is...
    • Opt. Lett. 40(6) 922-925 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Brad Deutsch

    • Testing the Maxwell-Boltzmann distribution using Brownian particles
    • Since the 1970's, optical tweezers have allowed us to manipulate tiny particles with focused laser beams. The electric field of such a beam "pulls" the particle toward its brightest point near the center. Since then,...
    • Opt. Express 23(2) 1888-1893 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Andrey N. Kuzmin

    • High peak power 4.7  ns electro-optic cavity dumped TEM00 1342-nm Nd:YVO4 laser
    • Continuously pumped four-level Q-switched Neodymium lasers operating at 1.3-μm exhibit high gain and are in highly demand for numerous applications. In particular, owing to moderate absorption by water and skin pigment...
    • Appl. Opt. 54(4) 717-720 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Brad Deutsch

    • Ultrafast oscilloscope based on laser-triggered field emitters
    • One of the most common electronic instruments in an undergraduate physics lab is an oscilloscope, which measures voltage as a function of time. The fastest oscillations we can measure with an oscilloscope depend on its...
    • Opt. Lett. 40(2) 260-263 (2015) View: Abstract | HTML | PDF

Optical Design and Instrumentation

  • Spotlight Summary by Roarke Horstmeyer

    • Multilayer four-flux matrix model accounting for directional-diffuse light transfers
    • Have you ever been fooled into thinking that a computer rendering of an object was the real thing? I certainly have. And the way research is progressing, I am quite sure it is only going to get more difficult to...
    • Appl. Opt. 55(1) 27-37 (2016) View: Abstract | HTML | PDF

  • Spotlight Summary by Jennifer D. T. Kruschwitz

    • TRACK – A new method for the evaluation of low-level extinction coefficient in optical films
    • A useful method for determining refractive index and very low absorption values in dielectric films only requires four simple spectrophotometric measurements: reflectance and transmittance at a low incidence angle, and...
    • Opt. Express 23(22) 28501-28521 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Justin Baba

    • Optical detection of glucose concentration in samples with scattering particles
    • Have you ever covered the output of a flashlight with cupped fingers and noticed that the diverging white light beam from the flashlight emerges from the back of your fingers as a uniform red glow? The uniformity, i.e.,...
    • Appl. Opt. 54(35) 10425-10431 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Paul Steinvurzel

    • Optical side scattering radiometry for high resolution, wide dynamic range longitudinal assessment of optical fibers
    • An old technique has been adapted to achieve unprecedented dynamic range and spatial resolution in measuring transmission loss of km-length photonic bandgap fibers. In side scatter radiometry, one end of an optical...
    • Opt. Express 23(21) 27960-27974 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Anton K. Vershovskii

    • Highly stable atomic vector magnetometer based on free spin precession
    • The most basic principle upon which quantum magnetometers rely is measuring the frequency of the Larmor precession – the precession of magnetic moment of the atom around a magnetic field. This frequency depends on the...
    • Opt. Express 23(17) 22108-22115 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by David M. Paganin

    • Wavefront measurement made by an off-the-shelf laser-scanning pico projector
    • Two things that particularly impress me, in any piece of research, are simplicity and cost effectiveness.

      (a) Simplicity, in the sense of a paper which reports a profoundly simple solution to a difficult...
    • Appl. Opt. 54(28) E235-E240 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Reinhard Völkel

    • Double-sided structured mask for sub-micron resolution proximity i-line mask-aligner lithography
    • “Is it possible to use a standard mask aligner in proximity mode to manufacture gratings with sub-200nm (half-pitch) resolution?” If you pose this question to any lithography expert, the answer will be simple and short:...
    • Opt. Express 23(13) 16628-16637 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Adam Mock

    • Energy transfer and visible–infrared quantum cutting photoluminescence modification in Tm-Yb codoped YPO4 inverse opal photonic crystals
    • As the world slowly transitions to renewable energy sources, solar photovoltaic devices will play a key role. Maximizing the light energy-to-electrical energy conversion in photovoltaic devices is key to successful...
    • Appl. Opt. 54(22) 6827-6831 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Richard Bowman

    • Ultrastable measurement platform: sub-nm drift over hours in 3D at room temperature
    • Instrument drift is the bane of experimental science; the more sensitive the instrument, the more important it becomes to stop the sample moving. Even the tiniest influence of air currents or temperature instabilities...
    • Opt. Express 23(13) 16554-16564 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Filippo Miatto

    • Bounds to precision for quantum interferometry with Gaussian states and operations
    • On the ultimate phase sensitivity: when less is more.

      Using one’s resources in the most efficient way possible is desirable for several reasons: we save time, we save efforts, we...
    • J. Opt. Soc. Am. B 32(7) 1354-1359 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Michael Zenou

    • Optically-controlled digital electrodeposition of thin-film metals for fabrication of nano-devices
    • Electronic devices are made layer by layer from the bottom up using additive methods to deposit conductors and dielectrics. Conventional processes usually include three main steps: deposition, patterning, and thickening...
    • Opt. Mater. Express 5(4) 838-848 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by David R. Busch

    • Fast silicon photomultiplier improves signal harvesting and reduces complexity in time-domain diffuse optics
    • Diffuse optical measurements of tissue inform clinicians of deep tissue hemodynamics continuously, without ionizing radiation or invasive proves. The most ubiquitous of these systems is the pulse-oximeter, which...
    • Opt. Express 23(11) 13937-13946 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Ergun Simsek

    • Spatially periodic modulation of optical conductivity in doped graphene by two-dimensional diffraction grating
    • Normally, diffraction gratings are large optical components (with respect to the wavelength of the incident light) composed of periodic structures. They have been used for many decades in lasers, monochromators,...
    • J. Opt. Soc. Am. B 32(4) 701-707 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Jean-Baptiste Masson

    • Cavity-enhanced optical Hall effect in two-dimensional free charge carrier gases detected at terahertz frequencies
    • The Optical Hall Effect (OHE) is the birefringence induced by the interaction of incident electromagnetic radiation with the free carriers in a material under a magnetic field. One of the uses of the OHE is the probing...
    • Opt. Lett. 40(12) 2688-2691 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Rudolf Saathof

    • Nanometer level characterization of the James Webb Space Telescope optomechanical systems using high-speed interferometry
    • Due to the perpetual pursuit to understand the origin of the universe, telescopes have continued to grow over the centuries in order to collect more light. Large telescopes make faint objects look brighter and otherwise...
    • Appl. Opt. 54(13) 4285-4298 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Georgi T. Georgiev

    • Establishment and application of the 0/45 reflectance factor scale over the shortwave infrared
    • The Bidirectional Reflectance Distribution Function (BRDF) is a fundamental quantity describing the reflectance properties of a target as a function of illumination and viewing geometries. However, there are only a few...
    • Appl. Opt. 54(10) 3064-3071 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Nadav Gutman

    • Optimal design of one-dimensional photonic crystal filters using minimax optimization approach
    • The ability to create optical bands occupies nowadays a prominent place in the toolbox of optical engineers. To design a basic one-dimensional photonic crystal with a pass or stop band, it is enough to apply a condition...
    • Appl. Opt. 54(6) 1399-1409 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Daniel Poitras

    • Spectral design of temperature-invariant narrow bandpass filters for the mid-infrared
    • Many properties of optical devices change with temperature: for example, laser light output shifts and broadens in wavelength, sensitivity and selectivity of sensors drop, efficiency varies. Even devices that are...
    • Opt. Express 23(1) 580-596 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Thomas Udem

    • Direct 15-GHz mode-spacing optical frequency comb with a Kerr-lens mode-locked Yb:Y2O3 ceramic laser
    • Mode-locked lasers that emit ultrashort pulses with a very large repetition rate are highly desirable for certain frequency comb applications. The team of Yohei Kobayashi at the University of Tokyo has now been able to...
    • Opt. Express 23(2) 1276-1282 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Ilya Shadrivov

    • Optical diffraction properties of multimicrogratings
    • Diffraction gratings are known to most of us from school, and they fascinate everyone with the colorful rainbows they can produce. Researchers in the United States used recent advances in nano-fabrication as well as a...
    • Appl. Opt. 54(7) 1808-1818 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Francesco Morichetti

    • Effect of injection current and temperature on signal strength in a laser diode optical feedback interferometer
    • Backreflections from the external world are among the worst enemies of lasers. Most people with some knowledge in optics are well aware of that. Optical feedback can induce fluctuations in the output power, lasing...
    • Appl. Opt. 54(2) 312-318 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Richard Bowman

    • Adjustable diffractive spiral phase plates
    • Light beams with a twisted spatial structure have many intriguing properties; their characteristic feature is that they carry orbital angular momentum, meaning they exert a torque on objects they illuminate in addition...
    • Opt. Express 23(1) 413-421 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Brad Deutsch

    • Ultrafast oscilloscope based on laser-triggered field emitters
    • One of the most common electronic instruments in an undergraduate physics lab is an oscilloscope, which measures voltage as a function of time. The fastest oscillations we can measure with an oscilloscope depend on its...
    • Opt. Lett. 40(2) 260-263 (2015) View: Abstract | HTML | PDF

Optics in Biology and Medicine

  • Spotlight Summary by Robert J. Zawadzki

    • Imaging pulse wave propagation in human retinal vessels using full-field swept-source optical coherence tomography
    • If you are wondering how the Optical Coherence Tomography (OCT) technology might evolve in the future, look no further than this latest article by Spahr et al. detailing clinical application of their Phase-Sensitive...
    • Opt. Lett. 40(20) 4771-4774 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Martin Villiger

    • Noninvasive, in vivo imaging of subcortical mouse brain regions with 1.7 μm optical coherence tomography
    • There are many tissues and organs that are more amenable to optical imaging than the brain. However, the prospect of observing neurons in action, investigating neurodegenerative diseases, studying brain tumors, or...
    • Opt. Lett. 40(21) 4911-4914 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Thomas Laurell and Henrik Bruus

    • Imaging local acoustic pressure in microchannels
    • Acoustofluidics is a rapidly growing area within the field of lab-on-a-chip and microfluidics. A driving force for this development is the immediate impact that microfluidic technology currently is having on fundamental...
    • Appl. Opt. 54(21) 6482-6490 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Shakil Rehman

    • Photonic non-contact estimation of blood lactate level
    • Under extreme circumstances, such as evading a life threatening situation or strenuous exercise, our bodies need more energy than the available level of oxygen can deliver. In such cases, the muscles generate energy...
    • Biomed. Opt. Express 6(10) 4144-4153 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Adam Hoppe and Brandon Scott

    • Pulse-shaping based two-photon FRET stoichiometry
    • The inner workings of living cells are made up of networks of proteins binding and releasing each other. A powerful approach to capture the orchestration of these events is imaging of Förster Resonance Energy Transfer...
    • Opt. Express 23(3) 3353-3372 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Shalin Mehta

    • Automated multi-parameter measurement of cardiomyocytes dynamics with digital holographic microscopy
    • High throughput screens are playing an increasingly important role in drug discovery pipelines. Lately, the field has been pushing towards optical measurement of biological function in live models of normal and diseased...
    • Opt. Express 23(10) 13333-13347 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Andreas Mandelis

    • Label-free imaging of melanoma with nonlinear photothermal microscopy
    • Nonlinear photothermal processes are interesting and important at both fundamental and applications levels. Thermal-wave fields, limited by the physics of parabolic diffusion, can only produce thermal gradient driven...
    • Opt. Lett. 40(7) 1141-1144 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Brad Deutsch

    • Determining the rotational mobility of a single molecule from a single image: a numerical study
    • Fluorescence microscopy is used to look at small samples that can't be seen clearly with a traditional light microscope. Transparent or very small materials like DNA strands can be tagged with fluorophores - fluorescent...
    • Opt. Express 23(4) 4255-4276 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Robert J. Zawadzki

    • Adaptive optics optical coherence tomography at 1 MHz
    • Almost 25 years after the first demonstration of optical coherence tomography (OCT), it is clear that the image acquisition speed offered by this now mature technology is one of the main parameters defining its present...
    • Biomed. Opt. Express 5(12) 4186-4200 (2014) View: Abstract | HTML | PDF

Optoelectronics

  • Spotlight Summary by Paul F. McManamon

    • Monostatic all-fiber scanning LADAR system
    • This work provides a robust example of a 3D lidar system that is ideal for small unmanned aerial vehicles (UAVs) and robots, but that could also find significant applications in gaming and in gathering data for 3D...
    • Appl. Opt. 54(33) 9752-9757 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Francesco Morichetti

    • Development of integrated mode reformatting components for diffraction-limited spectroscopy
    • Photonic dicers bring the light everywhere on a chip and light gets reformatted. This is indeed what we can do with the laser writing technique developed by D. MacLachlan and co-workers, enabling to build optical...
    • Opt. Lett. 41(1) 76-79 (2016) View: Abstract | HTML | PDF

  • Spotlight Summary by Taek Yong Hwang

    • 140-fs duration and 60-W peak power blue-violet optical pulses generated by a dispersion-compensated GaInN mode-locked semiconductor laser diode using a nonlinear pulse compressor
    • According to the uncertainty relation, the product of a pulse’s temporal width and that of its frequency spectrum is fundamentally required to be larger than a certain numerical constant, meaning that the generation of...
    • Opt. Express 23(25) 31766-31771 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Andrew Sarangan

    • In situ probing of mode-locked vertical-external-cavity-surface-emitting lasers
    • Can one probe a laser cavity to examine its sub-picosecond gain dynamics? This paper demonstrates a technique for doing exactly that using a femtosecond fiber laser as the probe. The large gain bandwidth of...
    • Opt. Lett. 40(23) 5459-5462 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Taek Yong Hwang

    • High-energy large-aperture Ti:sapphire amplifier for 5 PW laser pulses
    • Ultrafast lasers have contributed to expanding continuously our understanding of light-matter interactions with an increase in their peak power. Historically, to generate ultrafast laser pulses with a higher peak power,...
    • Opt. Lett. 40(21) 5011-5014 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Bharathwaj Narasimhan

    • New types of refractive-reflective aplanats for maximal flux concentration and collimation
    • Aplanatic systems have been of historical importance ever since Ernst Carl Abbe formulated the sine condition and its consequent implications on the elimination of certain aberration types resulting in significant...
    • Opt. Express 23(24) A1541-A1548 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by John Ballato

    • Limits in development of photonic crystal fibers with a subwavelength inclusion in the core
    • Every reader will appreciate the utility of optical fibers as a technology platform. It seems perhaps less well appreciated that optical fibers can themselves also serve as an enjoyable small laboratory for the study of...
    • Opt. Mater. Express 5(10) 2366-2376 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Andrey N. Kuzmin

    • Quantum dot lasers for silicon photonics [Invited]
    • Silicon photonics is an optical analogue of silicon microelectronics. This area provides leading technological solutions for applications of integrated photonics, such as high performance computing and optical...
    • Photon. Res. 3(5) B1-B9 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Francesco Marsili

    • Ultimate low system dark-count rate for superconducting nanowire single-photon detector
    • Superconducting nanowire single photon detectors (SNSPDs) have recently reached near-unity system detection efficiency (1S) in the near infrared, which triggered a surge of breakthroughs in quantum optics. For many...
    • Opt. Lett. 40(14) 3428-3431 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Uwe Brauch

    • Two-dimensional pseudo-random optical phased array based on tandem optical injection locking of vertical cavity surface emitting lasers
    • The coherent superposition of laser beams – at least in principle – can solve two major challenges in one go:

      1. the scaling of the output power while conserving diffraction-limited beam quality, and...
    • Opt. Express 23(15) 19405-19416 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Taek Yong Hwang

    • Optimizing average power in low quantum defect lasers
    • Given their many applications in material processing, remote sensing, defense, and fundamental science, lasers have undergone a tremendously fast development. This has included a constant increase in output powers, both...
    • Appl. Opt. 54(31) F78-F84 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Andrey N. Kuzmin

    • Gain and loss as a function of current density and temperature in interband cascade lasers
    • Since the first experimental realization of an interband cascade laser (ICL) in 1997, this device has become a leading portable light source for the mid-infrared (IR) light wavelength range due of its low drive power...
    • Appl. Opt. 54(31) F1-F7 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Bernhard Schmauss

    • Two-fold transmission reach enhancement enabled by transmitter-side digital backpropagation and optical frequency comb-derived information carriers
    • Today, optical fiber telecommunication systems are based on high-order modulation formats, coherent detection schemes, digital signal processing and channel coding techniques to fulfill the ever increasing demands for...
    • Opt. Express 23(16) 20774-20783 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Zetian Mi

    • Heterogeneous integration of gallium nitride light-emitting diodes on diamond and silica by transfer printing
    • Thermal management is crucial for the stable and efficient operation of GaN-based light-emitting diodes (LEDs), since considerable heat is generated, particularly at high power operation. Increased junction temperature...
    • Opt. Express 23(7) 9329-9338 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by József A. Fülöp

    • Ultrafast imaging of terahertz Cherenkov waves and transition-like radiation in LiNbO3
    • Visualizing a phenomenon is often an important driving force for scientific results and new measurement techniques. It is probably the best way also for learning and understanding. The work of Frank Hegmann’s group on...
    • Opt. Express 23(6) 8073-8086 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Tomas Cizmar

    • Delivery of focused short pulses through a multimode fiber
    • The article by Delgado et al. presents the delivery of focused 500 fs pulses through a 30 cm long multimode fiber. This represents an important first step towards multiphoton imaging via a multimode fiber-based...
    • Opt. Express 23(7) 9109-9120 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Stephen Madden

    • Experimental demonstration of propagation characteristics of mid-infrared photonic crystal waveguides in silicon-on-sapphire
    • The work undertaken in the paper of Zou et al. is in its basic essence the realisation of Mid-infrared guiding slow light photonic crystal (PC) waveguides on a solid sapphire substrate rather than the typical membrane...
    • Opt. Express 23(5) 6965-6975 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Roarke Horstmeyer

    • Matrix formalism for light propagation and absorption in thick textured optical sheets
    • Solar power must be cost effective to compete with non-renewable sources of energy. While economies of scale are quickly driving down the cost of more conventional solar panel designs, there is still plenty of room to...
    • Opt. Express 23(11) A502-A518 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Holger Wittel

    • Actuation profiles to form Zernike shapes with a thermal active mirror
    • Improving lithography is a key factor for producing more powerful microprocessors, and lithography using extreme ultraviolet (EUV) radiation is being developed for this purpose. This paper aims to overcome one of the...
    • Opt. Lett. 40(2) 205-208 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Andrey N. Kuzmin

    • High peak power 4.7  ns electro-optic cavity dumped TEM00 1342-nm Nd:YVO4 laser
    • Continuously pumped four-level Q-switched Neodymium lasers operating at 1.3-μm exhibit high gain and are in highly demand for numerous applications. In particular, owing to moderate absorption by water and skin pigment...
    • Appl. Opt. 54(4) 717-720 (2015) View: Abstract | HTML | PDF

Vision and Color

  • Spotlight Summary by Shakil Rehman

    • Human skin detection in the visible and near infrared
    • Distinguishing a human body from its surroundings through light reflection from skin is a formidable task in search-and-rescue operations and computer vision. The authors of this Applied Optics article propose a...
    • Appl. Opt. 54(35) 10559-10570 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Robert J. Zawadzki

    • Imaging translucent cell bodies in the living mouse retina without contrast agents
    • Despite very impressive advances made over the last two decades in the field of in vivo retinal imaging, visualization of many cell classes remains elusive due to a lack of intrinsic optical contrast. To overcome this...
    • Biomed. Opt. Express 6(6) 2106-2119 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Jason Porter

    • Adaptive-optics SLO imaging combined with widefield OCT and SLO enables precise 3D localization of fluorescent cells in the mouse retina
    • The mouse has become a desirable model for experiments designed to better understand normal and diseased retinal structure and function due to the ability to label specific cell classes and genetically modify retinal...
    • Biomed. Opt. Express 6(6) 2191-2210 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Shakil Rehman

    • LCD-based digital eyeglass for modulating spatial-angular information
    • Display technology is a ubiquitous part of our everyday life. We spend a considerable part of our waking time in front of a screen, such as working on a computer, watching TV, using mobile devices such as a tablets and...
    • Opt. Express 23(9) 11813-11818 (2015) View: Abstract | HTML | PDF

  • Spotlight Summary by Kedar Khare

    • Thermal-to-visible face recognition using partial least squares
    • Automated face recognition has been an active research area for several decades, with multiple applications in biometrics and security. Typically a database of face images is stored and a suitable mathematical scheme is...
    • J. Opt. Soc. Am. A 32(3) 431-442 (2015) View: Abstract | HTML | PDF

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