Early Posting

Accepted papers to appear in an upcoming issue

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Surface Plasmon Resonance Temperature Sensor based on the Conjoined-Tube Hollow-Core Anti-Resonant Fiber with Ultra-High Temperature Sensitivity

Haihao Fu, Zijuan Tang, wei gao, Yuying Guo, Paul Chu, and shuqin lou

DOI: 10.1364/JOSAB.517575 Received 02 Jan 2024; Accepted 26 Feb 2024; Posted 29 Feb 2024  View: PDF

Abstract: A surface plasmon resonance (SPR) temperature sensor based on the conjoined-tube hollow-core anti-resonant fiber (HC-ARF) is designed and analyzed. The conjoined-tube HC-ARF contains two connecting tubes with a cross arrangement in the cladding. The SPR temperature sensor is constructed by inserting a metal into one of the inner layer tubes and injecting a thermo-sensitive liquid into the hollow core of the HC-ARF to enhance the temperature sensitivity by exploiting the SPR effect. The effects of the structural parameters and thermo-sensitive media and metals on the sensing properties such as the temperature sensitivity, peak loss, resolution, amplitude sensitivity, and figure of merit (FOM) are analyzed systematically. Numerical analysis reveals ultra-high temperature sensitivity of 38.8 nm/℃ and FOM of 673.84 ℃-1, which are approximately ten times higher than those of sensors described in the recent literature. In addition, the sensor is capable of detecting a wide temperature range from -5 ℃ to 60 ℃ with good linearity. The novel SPR temperature sensor with high precision, a wide temperature detection range, a simple and easily modifiable structure, as well as good manufacturing tolerance has large potential in high-precision temperature monitoring in the petrochemical and biomedical industries.

Modulation of the band gap and enhancement of the third-order optical nonlinearity in vanadium-doped SrSnO3 films

Ziheng Huang, Depeng Wang, Ruifeng Niu, and Weitian Wang

DOI: 10.1364/JOSAB.516798 Received 21 Dec 2023; Accepted 25 Feb 2024; Posted 26 Feb 2024  View: PDF

Abstract: Perovskite oxide vanadium-doped SrSnO3 (SrSn1-xVxO3) thin films with different concentrations x = 0.1~0.9 were fabricated by using pulsed-laser deposition, and the effects of V doping on the structure, optical band gap and the third-order optical nonlinearity were systematically investigated. With the increase of x value, the lattice parameters of SrSn1-xVxO3 decrease from 3.997 to 3.862 Å gradually, while the optical band gaps firstly increase and then decrease with boundary at x = 0.3. The third-order nonlinear optical responses were studied via the z-scan technique. The closed-aperture measurements show a negative nonlinear refractive index n2, and the open-aperture measurements demonstrate a saturable absorption β. Both the n2 and β responses vary with the increase of V doping level. The metal-oxygen chemical bond along with the localized V5+Sn2+V5+ complex contribute to the enhancement of optical nonlinearity, and the highest value of third-order susceptibility χ(3) is observed in SrSn0.5V0.5O3 film.

Simultaneous Measurement of SRI and Temperature Using Local Micro-Structured LPFG Sensor Operating near PMTP

Ying Wang, Zhengyuan Li, Bo Pang, xinyu wang, Yihao He, Jinghong Zhang, Leaven Romeo Mupfukirei, Kai Zhang, qiang ling, Zhangwei Yu, and Daru Chen

DOI: 10.1364/JOSAB.517146 Received 27 Dec 2023; Accepted 25 Feb 2024; Posted 26 Feb 2024  View: PDF

Abstract: We have proposed a novel local-micro-structured long period fiber grating (LMSLPFG) sensor near the phase-matching turning point (PMTP) for simultaneous measurement of surrounding refractive index (SRI) and temperature. By using the HF solution or Femtosecond laser to partially change the cladding radius of LPFG, the LMSLPFG is realized. Such change affects the effective refractive index of cladding mode and further causes a new resonant peak in the spectrum. By using the transfer matrix method, the formation mechanism of the peak in the middle of the LMSLPFG transmission spectrum corresponding to a little off-resonant state (ALOR) near PMTP and the other two peaks on both sides corresponding to the dual-peak resonance are studied. On this basis, the sensing characteristics of such three resonant peaks to SRI and temperature are analyzed. When the SRI and temperature change, the transmissivity of the peak in ALOR changes without response occurring at resonant wavelength, while the wavelength of other two dual peaks will respond proportionately. The numerical simulations results demonstrate that the sensitivities of the distance between the dual peaks to SRI and temperature are 777.14 nm/RIU and -0.22 nm/℃, respectively, and the sensitivities of single peak transmissivity to SRI and temperature are -394.06 dB/RIU and 0.05 dB/℃, respectively. Therefore, the sensitivity matrix can be used to measure SRI and temperature simultaneously with a single LMSLPFG.

Random telegraph dispersion-management: modulational instability

Andrea Armaroli and Matteo Conforti

DOI: 10.1364/JOSAB.511931 Received 10 Nov 2023; Accepted 25 Feb 2024; Posted 26 Feb 2024  View: PDF

Abstract: We study modulational instability in a fiber system resembling a dispersion-managed link where the sign of the group-velocity dispersion varies randomly according to a telegraphprocess. We find that the instability gain of stochastic origin converges, for long fiber segmentmean length (the inverse of the transition rate between the two values), to the conventional valuesfound in a homogeneous anomalous dispersion fiber. For short fiber segments, the gain bands arebroadened and the maximum gain decreases. By employing correlation splitting formulas, weobtain closed form equations that allow us to estimate the instability gain from the linearizednonlinear Schrödinger equation. We compare the analytical to the numerical results obtained in aMonte Carlo spirit. The analysis is proven to be correct not only for a fluctuating group-velocitydispersion, but also including fourth-order dispersion (both constant or varying according to asynchronous or independent telegraph process). These results may allow researchers to tailorand control modulational instability sidebands, with applications in telecommunications andparametric photon sources.

Spectral stability of a synchronously pumped optical parametric oscillator with a spatially dispersed beam

Keisuke Nagashima, Nobuhisa Ishii, and Ryuji Itakura

DOI: 10.1364/JOSAB.515148 Received 04 Dec 2023; Accepted 24 Feb 2024; Posted 26 Feb 2024  View: PDF

Abstract: This study reports the spectral stability of a synchronously pumped optical parametric oscillator with a spatially dispersed beam. Using this method, broadband phase matching can be realized at any wavelength. However, large spectral fluctuations were observed in the signal pulses. Here, we demonstrate a stable condition under which the signal pulses have no spectral instabilities or pulse-to-pulse fluctuations. This stable condition was found through numerical simulations and confirmed experimentally.

Propagation dynamics of the Hermite-Gaussian beam in the fractional Schrödinger equation with different potentials

Chao Tan, Yong Liang, Min Zou, Tong Lei, Pinghua Tang, and Mingwei Liu

DOI: 10.1364/JOSAB.519072 Received 17 Jan 2024; Accepted 22 Feb 2024; Posted 22 Feb 2024  View: PDF

Abstract: We have studied the propagation dynamics of the Hermite-Gaussian (HG) beam in the fractional Schrödinger system with linear, parabolic, and Gaussian potentials. The results show that the splitting of the beam without an external potential is influenced by the Lévy index. The splitting phenomenon disappears and a periodic evolution of the HG beam occurs when a linear potential is added to the equation. A shorter evolution period is shown with a larger linear potential coefficient, and its sign affects laser beam’s deflection direction. The transverse amplitude of HG beams is proportional to Lévy index. When taking into account a parabolic potential, the beam exhibits autofocus effect during propagation. For a larger Lévy index, the focusing speed gets faster and the focal intensity is weakened. In addition, the transverse amplitude is smaller and the focusing speed is faster with a larger parabolic potential coefficient. In a Gaussian potential, the diffraction effect of the beam grows more pronounced as the Lévy index increases, which leads to a chaotic phenomenon in the beam. The propagation of HG beams is controlled by regulating the Gaussian potential height, potential width, and position of the potential. It is also found that the total reflectivity of the Gaussian potential barrier is stronger than the potential well for same parameters. These features are significant for applications of optical communications, optical devices and laser design.

Ultrafast random polarization beam smoothing driven by rotating wavefront via optical Kerr effect

hao xiong, Zheqiang Zhong, and Bin Zhang

DOI: 10.1364/JOSAB.495471 Received 16 May 2023; Accepted 21 Feb 2024; Posted 22 Feb 2024  View: PDF

Abstract: We propose an ultrafast random polarization smoothing scheme to enhance irradiation uniformity and randomize polarization of the focal spot. In the scheme, each beamlet in a laser quad is driven by a rotating petal-like wavefront, giving rise to the ultrafast redistribution of the speckles within the focal spot and thus improving the irradiation uniformity of the focal spot. The rotating wavefront is induced by an optical Kerr medium pumbed by a laser beam with rotating intensity distribution that is generated by the superposition of two Laguerre-Gaussian beams carrying conjugate vortex phase and frequency shift. In addition, by properly selecting the topological charges of the pump beams and polarization states of the beamlets, the beamlets in a quad can be divided into two sets with counter-rotating wavefronts and orthogonal polarizations, which further randomizes the polarization of the focal spot. The ultrafast random polarization smoothing scheme is expected to improve the beam smoothing and polarization randomizing performance.

Electromagnetic field quantization in the presence of a moving nano-particle

Vahid Ameri, Alidad Askari, Morteza rafiee, and M Eghbali-Arani

DOI: 10.1364/JOSAB.517013 Received 08 Jan 2024; Accepted 21 Feb 2024; Posted 22 Feb 2024  View: PDF

Abstract: An appropriate Lagrangian is considered for a system comprising a moving nanoparticle in a semi-infinite space, and the electromagnetic and matter fields are quantized. Through an analysis of the absorbed power radiation, it is demonstrated that the quantum friction experienced by high-velocity nanoparticles can be identified as a dissipative term in the radiation power of the nanoparticle. The absorbed power radiation for a moving nanoparticle is derived and compared with that of a static one. By considering two different temperature scenarios, it is explicitly shown that the absorbed power radiation for a moving nanoparticle always contains a negative term in its power spectrum, which can be attributed to the power lost due to non-contact quantum friction.

Exact solution of a lambda quantum system driven by a two-photon wavepacket

Daniel Valente and Wendel Lopes da Silva

DOI: 10.1364/JOSAB.515618 Received 12 Dec 2023; Accepted 20 Feb 2024; Posted 21 Feb 2024  View: PDF

Abstract: Three-level atoms in lambda configuration find diverse applications in quantum information processing, and a promising way to manipulate their quantum states is with single-photon pulses propagating in a waveguide (which can be theoretically regarded as a highly broadband regime of the Jaynes-Cummings model). Here, we analytically find the non-perturbative dynamics of a lambda atom driven by a two-photon wavepacket, propagating in a one-dimensional electromagnetic environment. As an application, we study the dynamics of a quantum state purification. By comparing our exact model with an approximated model of two cascaded single-photon wavepackets, we show how two-photon nonlinearities and stimulated emission affect the purification.

Neural network method: Withstanding noise for continuous-variable quantum key distribution with discrete modulation.

dingmin Cheng, Yewei Guo, jiayang Dai, Hao Wu, and Ying Guo

DOI: 10.1364/JOSAB.509184 Received 18 Oct 2023; Accepted 20 Feb 2024; Posted 21 Feb 2024  View: PDF

Abstract: Excess noise in continuous-variable quantum key distribution (CVQKD) systems usually results in a loss of key rate, leading to fatal security breaches. This paper proposes a long short-term memory (LSTM) time-sequence neural network to predict the key rate of the system while counteracting the effects of excess noise. The proposed network model, which can be updated with historical data, predicts the key rate of the future moment for the input time-sequence data. To increase the key rate we perform a post-selection operation to combat excess noise. We demonstrate the asymptotic security of the protocol against collective attacks with the numerical simulations using the QPSK (quadrature phase-shift keying) protocol, where some parameters have been optimized to resist excess noise. It provides a potential solution for improving the security of quantum communication in practical applications.

Versatile Terahertz metasurfaces: Dynamic Switching Between Electromagnetically Induced Transparency and Perfect Absorption

shuzhao Zhang, Yunping Qi, Zhou zihao, Qiang Shi, Li Wang, and Bing Luo

DOI: 10.1364/JOSAB.510254 Received 25 Oct 2023; Accepted 18 Feb 2024; Posted 21 Feb 2024  View: PDF

Abstract: This paper introduces a versatile metasurface based on vanadium dioxide (VO₂) and graphene that seamlessly transitions between Electromagnetically Induced Transparency (EIT) and multi-band absorption through the VO₂’s phase change property. As VO₂ is in dielectric state, the device can generate EIT. This configuration allows dynamic tuning of the central frequency by adjusting the graphene’s Fermi levels (𝐸𝑓), achieving a remarkable group delay of 1.42 ps. As VO₂ is in metallic state, the structure facilitates a Fabry-Perot resonance between the VO₂ layer at the bottom and the graphene layer at the top, leading to exceptional light absorption. Specifically, absorptivity of 99.8% and 98.4% are achieved at 1.66 THz and 2.87 THz, respectively. In addition, these two resonance peaks can also be dynamically adjusting by modulating 𝐸𝑓.Furthermore, the device serves as a highly sensitive sensor with sensitivity up to 0.65 THz/RIU. Notably, both absorption and EIT modes are polarization-insensitive and exhibit tolerance to a wide range of incidence angles. Consequently, the proposed device holds significant promise across various applications within the electromagnetic field, including tunable devices, absorbers, senors, slow-light devices and so on.

Narrowband terahertz generation in a plane-parallel Rb:KTP crystal using a phase mask

Yuri Avetisyan and Armen Makaryan

DOI: 10.1364/JOSAB.514985 Received 04 Dec 2023; Accepted 17 Feb 2024; Posted 21 Feb 2024  View: PDF

Abstract: A scheme for efficient generation of multi-cycle terahertz pulses by optical rectification in artificial periodically poled rubidium (Rb)-doped potassium titanyl phosphate (Rb:PPKTP) structure is proposed. The structure consists of a multi-slit phase mask placed in front of a large-aperture Rb:KTP crystal. The developed theory predicts the THz pulses energy of 343 μJ and the efficiency of the pump-to-terahertz conversion of 0.44% for pump pulse peak intensity of 70 GW/cm² inside an aperture of 9.4 × 15 mm² at a crystal temperature of 85 K. The opportunity to control the THz spectral bandwidth (in the range of 1.8% ÷ 85%) and frequency of the generation (from 0.3 to 0.8 THz) is shown. The results of the study indicate the high potential of the artificial Rb:PPKTP structure for tunable high-energy THz generation.

Photon subtraction with Mach-Zehnder interferometerand its application to entanglement enhancement

Shengli Zhang, Song Yang, and JingTing Ma

DOI: 10.1364/JOSAB.518234 Received 08 Jan 2024; Accepted 17 Feb 2024; Posted 21 Feb 2024  View: PDF

Abstract: Photon subtraction (PS) is an important operation for optic quantum informationprocessing. Conventional photon subtraction is implemented with a singlelinear beam splitter (BS) and photon detector. However, in this study, weshow that the performance of photon subtraction can be enhanced with twobeam splitters and an optional phase modulator. This can be considered asphoton subtraction with an extended version of the well-known Mach-Zehnder(MZ) interferometer. By tuning the transmittance of the two beam splitters and phase modulator, the probability of success can be greatly improvedcompared with the original with single beam splitter and photon detector.Moreover, if applied to a single photon input, our proposed scheme can even implement deterministic photon subtraction, which is almost impossible for original scheme with single BS and photon detection. Owing to the higher probability of success,it is straightforward to apply the PSMZ method to entanglement enhancement of very weak two-mode squeezed vacuum state. Our resultis helpful for improving the yield of output entanglement.

One- and Two-Dimensional Electromagnetically Induced Grating in a Microwave-Driven M-type atomic system

Anju Pal, Zubair Dar, and Paramjit Kaur

DOI: 10.1364/JOSAB.517644 Received 02 Jan 2024; Accepted 17 Feb 2024; Posted 22 Feb 2024  View: PDF

Abstract: In this paper, we theoretically investigate a scheme for both 1D and 2D electromagnetically induced gratings (EIG) in M-type atomic systems in which two ground states are coupled by a microwave field. It is observed that the presence of a microwave field enhances the probe diffraction efficiency to higher orders, thus leading to the construction of phase gratings in 1D and 2D cases. The study shows that changingthe system parameters numerically, such as the strength of the applied microwave field, standing wave field, and length of the atomic medium, leads to modulation of diffraction efficiency into higher orders. The application of microwave fields is a more convenient parameter for attaining increased first-order diffraction. We believe that the proposed system with a microwave field can be used for designing novel microwave sensing devices for networking and communication.

Fabrication uncertainty aware and robust design optimization of a photonic crystal nanobeam cavity by using Gaussian processes

Matthias Plock, Felix Binkowski, Lin Zschiedrich, Philipp-Immanuel Schneider, and Sven Burger

DOI: 10.1364/JOSAB.505767 Received 15 Sep 2023; Accepted 16 Feb 2024; Posted 21 Feb 2024  View: PDF

Abstract: We present a fabrication uncertainty aware and robust design optimization approach that can be used to obtain robust design estimates for nonlinear, nonconvex, and expensive model functions. It is founded on Gaussian processes and a Monte Carlo sampling procedure, and assumes knowledge about the uncertainties associated with a manufacturing process. The approach itself is iterative. First, a large parameter domain is sampled in a coarse fashion. This coarse sampling is used primarily to determine smaller candidate regions to investigate in a second, more refined sampling pass. This finer step is used to obtain an estimate of the expected performance of the found design parameter under the assumed manufacturing uncertainties. We apply the presented approach to the robust optimization of the Purcell enhancement of a photonic crystal nanobeam cavity. We obtain a predicted robust Purcell enhancement of F ≈ 3.3. For comparison we also perform an optimization without robustness. We find that an unrobust optimum of F ≈ 256.5 dwindles to only F ≈ 0.7 when fabrication uncertainties are taken into account. We thus demonstrate that the presented approach is able to find designs of significantly higher performance than those obtained with conventional optimization.

Accelerating Finite-Difference Frequency-Domain Simulations for Inverse Design Problems in Nanophotonics using Deep Learning

Lukas Schulte, Marco Butz, Marlon Becker, Benjamin Risse, and Carsten Schuck

DOI: 10.1364/JOSAB.506159 Received 18 Sep 2023; Accepted 15 Feb 2024; Posted 16 Feb 2024  View: PDF

Abstract: Inverse design of nanophotonic devices becomes increasingly relevant for the development of complex photonic integrated circuits. Electromagnetic first-order simulations contribute the overwhelming computational cost to the optimization routines in established inverse design algorithms, requiring more efficient methods for enabling improved and more complex design process flows. Here we present such a method to predict the electromagnetic field distribution for pixel-discrete planar inverse designed structures using deep learning. Our model is able to infer accurate predictions used to initialize a conventional Finite Difference Frequency-Domain-algorithm and thus lowers the time required for simulating the electromagnetic response of nanophotonic device layouts by about 50 %. We demonstrate the applicability of our deep learning method for inverse design of photonic integrated powersplitters and mode convertersand we highlight the possibility of exploiting previous learning results in subsequent design tasks of novel functionalities via finetuning on reduced data sets, thus improving computational speed further.

Influence of correlations in active medium on pump-induced exceptional points and strong coupling

Iryna Pashkevich, Ilya Doronin, Alexander Zyablovsky, and Evgeny Andrianov

DOI: 10.1364/JOSAB.516839 Received 21 Dec 2023; Accepted 14 Feb 2024; Posted 16 Feb 2024  View: PDF

Abstract: Exceptional points show great prospects for applications such as imaging, sensing and designing lasers. Recently, systems with amplifying active medium exhibiting pump-induced exceptional points have attracted much attention due to possibility of controlling strong coupling between light and matter with the aid of pumping. In such structures, the interaction of active molecules with external degrees of freedom, such as phonons or impurities, leads to the destruction of correlations between polarizations of different molecules. We study the effect of the correlation decay on a system behavior near the pump-induced exceptional point. We show that strong coupling persists and eigenvectors together with eigenfrequencies coalesce at a negative value of population inversion, regardless of correlation decay magnitude. Thus, we show that exceptional points are robust to correlation decay, which is crucial for designing systems with exceptional points.

Observation of dual-band bound states in the continuum emerged from Mie surface lattice resonances

Rixing Huang, Xueqian Zhao, Zhang Zhenrong, and Guangyuan Li

DOI: 10.1364/JOSAB.514782 Received 29 Nov 2023; Accepted 13 Feb 2024; Posted 13 Feb 2024  View: PDF

Abstract: Surface lattice resonances (SLRs) and bound states in the continuum (BICs) are two exciting approaches for achieving high quality factors in metasurfaces. BICs emerged from SLRs have raised great interest for not only the ultrahigh quality factors but also the nonlocal field enhancement. However, experimental demonstrations remain insufficient due to the material absorption or the inappropriate parameter design. Here we experimentally demonstrate dual-band symmetry-protected BICs emerged from Mie SLRs in all-dielectric metasurfaces. We attribute these dual-band BICs to the zero emission at Γ point for the in-plane electric quadrupole and out-of-plane magnetic dipole SLRs, respectively. Such BICs feature nonlocal field enhancement and convenient spectral tunability, which are inheritage of SLRs. We expect such nonlocal metasurfaces supporting BICs will find applications especially in nanolasers, nonlinear optics and biochemical sensing.

Sorting, Trapping and Shifting of Microparticles with Stagnation Point Flow on an Optofluidic Chip

Xiaofang Huang, Yihang Huang, Wenshuo Mai, hang zhang, and Sha Xiong

DOI: 10.1364/JOSAB.510477 Received 26 Oct 2023; Accepted 12 Feb 2024; Posted 13 Feb 2024  View: PDF

Abstract: This paper proposes an optofluidic chip for highly efficient and multipurpose microparticle manipulation including sorting, trapping and shifting. The microparticles are confined by hydrodynamic focusing and conveyed to the optical active region, where the particles are slowed down by stagnation flow. Low velocity prolongs the acting time, allowing optical sorting with high efficiency by a laser of moderate power. Numerical simulations are utilized to optimize the flow rates for hydrodynamic focusing and stagnation point flow. Experiments have demonstrated the sorting of polystyrene particles with a diameter of 3.2-μm from those of 1.1-μm. In addition, we have realized the trapping of single 3.2-μm particle with controllable equilibrium positions. Velocity variation of the microparticles has been analyzed during the manipulation process. The proposed design presents a new alternative to meet the sorting performance, target selectivity, throughput, and versatility of an integrated device in biomedical applications.

Photonic crystal fiber sensors to excite surface plasmon resonance based on elliptical detection channels are used for highly sensitive magnetic sensing

Hujun Tang, Feifei Sun, Tao Shen, Feng Yue, Chi Liu, Xin Liu, and Chao Wang

DOI: 10.1364/JOSAB.506522 Received 21 Sep 2023; Accepted 03 Feb 2024; Posted 08 Feb 2024  View: PDF

Abstract: To improve the detection performance of fibre optic magnetic field sensors a new photonic crystal fiber (PCF) based on surface plasmon resonance (SPR) was designed and investigated. The designed sensor uses an elliptical detection channel, and the modal transmission characteristics and magnetic field sensing characteristics of this fiber optic sensor are analyzed using the Full Vector Finite Element Method (FVFEM). In addition, the effect of the detection channel on the detection accuracy at different curvatures was investigated. Compared with previous optical fiber magnetic field (MF) sensors, the designed sensor meets the requirements of both refractive index (RI) and MF measurements, and the MF sensitivity, refractive index (RI) sensitivity, and amplitude sensitivity (AS) of the sensor reach 0.739 nm/Oe,12043.8nm/RIU, and 754.88 RIU-1, respectively. The designed sensor expands the application range of optical fiber sensors and reduces the cost. It has great potential for application in complex environments.

Investigation of graphene supported sub-millimeter adjustable metamaterial absorbers

Shizeng Jiang, Duo Cao, Shilin Liu, Yan Cheng, Jiaxin Li, Lianhao He, Fangting Lin, Feng Liu, and Xiaoyong He

DOI: 10.1364/JOSAB.517952 Received 08 Jan 2024; Accepted 02 Feb 2024; Posted 05 Feb 2024  View: PDF

Abstract: Based on the graphene ribbons resonator, the tunable resonant properties of metamaterials (MMs) have been symmetrically investigated in the submillimeter region, including the effects of graphene Fermi levels, rotation angles, incident angles and polarization angles. The results manifest that the proposed graphene ribbon MMs indicates a high Q-factor of more than 20. The Fermi level affects the resonant curves significantly, obvious resonant peaks can be observed if the Fermi level is larger than 0.20 eV, and the resonant strength increases with Fermi level. For instance, for the single graphene ribbons, the absorption modulation depth (MD) is about 22.60% on the condition that the Fermi level changes in the range of 0.1-1.0 eV, and the absorption amplitude MD reaches about 93.85% if the rotation angles of the graphene ribbon degree changes in the range of 0-90 degrees. Additionally, by utilizing the triple graphene ribbons with different lengths, multiple resonant peaks (0.22 THz, 0.345 THz, and 0.46 THz) can be achieved simultaneously. Apart from the good tunable properties, the amplitude MD is about 76.6% (82.18%) if the incident (polarization) angle of the THz wave changes in the range of 0-90 degrees. These results can help us to better understand the tunable mechanisms of graphene metamaterials and design novel high performances devices such as light absorbers, detectors, and sensors.