Abstract

Due to the high performance and low cost, spintronic terahertz emitters (STEs) have been a hot topic in the field of terahertz sources. However, most of the research focuses on the THz generation process and little attention has been paid to the control and modulation of the THz wave generated by the STE. In this Letter, a unidirectional spintronic terahertz emitter (USTE) integrating a common STE with a metal grating is proposed to manipulate the THz emission process. The dyadic Green’s function method and finite element method are adopted to survey the characteristics of the USTE. Simulations show that the metal grating not only has a transmission larger than 97% in the optical band, but also has a higher reflectivity larger than 99% in the THz band. As a result, the USTE has a unidirectional THz emission along the direction of the pump beam with a larger than 4-fold enhancement in intensity. Moreover, the USTE has the capability of tuning the central frequency and THz wave steering by adjusting the distance and angle between the STE and the metal grating. We believe that this USTE can be used in THz wireless communications and holographic imaging, especially in the field of THz bio-sensing, which needs some resonance frequencies to sense.

© 2022 Optica Publishing Group

Average power scaling of THz spintronic emitters efficiently cooled in reflection geometry

Tim Vogel, Alan Omar, Samira Mansourzadeh, Frank Wulf, Natalia Martín Sabanés, Melanie Müller, Tom S. Seifert, Alexander Weigel, Gerhard Jakob, Mathias Kläui, Ioachim Pupeza, Tobias Kampfrath, and Clara J. Saraceno
Opt. Express 30(12) 20451-20468 (2022)

Fiber-tip spintronic terahertz emitters

Felix Paries, Nicolas Tiercelin, Geoffrey Lezier, Mathias Vanwolleghem, Felix Selz, Maria-Andromachi Syskaki, Fabian Kammerbauer, Gerhard Jakob, Martin Jourdan, Mathias Kläui, Zdenek Kaspar, Tobias Kampfrath, Tom S. Seifert, Georg von Freymann, and Daniel Molter
Opt. Express 31(19) 30884-30893 (2023)

Solid-state biased coherent detection of ultra-broadband terahertz pulses generated in a spintronic emitter for high repetition rate, low pulse energy lasers

Tim Suter, Alessandro Tomasino, Matteo Savoini, Sarah Houver, Roberto Morandotti, Steven L. Johnson, and Elsa Abreu
Opt. Express 30(25) 45202-45211 (2022)

Efficient unidirectional SPP launcher: coupling the SPP to a smooth surface for propagation

Wenjie Liu, Guoxuan Wang, Kunhua Wen, Xiaolong Hu, and Yuwen Qin
Opt. Lett. 47(3) 621-624 (2022)

Modulating the polarization of broadband terahertz pulses from a spintronic emitter at rates up to 10 kHz

Oliver Gueckstock, Lukáš Nádvorník, Tom S. Seifert, Martin Borchert, Gerhard Jakob, Georg Schmidt, Georg Woltersdorf, Mathias Kläui, Martin Wolf, and Tobias Kampfrath
Optica 8(7) 1013-1019 (2021)