Enhanced terahertz detection of multigate graphene nanostructures

Nanophotonics

Delgado-Notario Juan A.¹  Knap Wojciech¹  Taniguchi Takashi²  Popov Vyacheslav V.³  Fateev Denis V.³  Velázquez-Pérez Jesús E.⁴  Diez Enrique⁴  Meziani Yahya M.⁴  Salvador-Sánchez Juan⁴  Clericò Vito⁴  Calvo-Gallego Jaime⁴  Watanabe Kenji⁵  Otsuji Taiichi⁶ 

[1] CENTERA Laboratories, Institute of High Pressure Physics, Polish Academy of Sciences, 29/37 Sokołowska Str, Warsaw, Poland;International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba305-0044, Japan;Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), Russian Academy of Sciences, Saratov410019, Russia;Nanotechnology Group, USAL-Nanolab, Universidad de Salamanca, Plaza de la Merced, Edificio Trilingüe, 37008, Salamanca, Spain;Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba305-0044, Japan;Research Institute of Electrical Communication, Tohoku University, Sendai980-8577, Japan;

关键词: 2d materials;    field effect transistor;    graphene;    nano-photodetector;    plasmonics;    terahertz;   

DOI  :  10.1515/nanoph-2021-0573

来源: DOAJ

【 摘 要 】

Terahertz (THz) waves have revealed a great potential for use in various fields and for a wide range of challenging applications. High-performance detectors are, however, vital for exploitation of THz technology. Graphene plasmonic THz detectors have proven to be promising optoelectronic devices, but improving their performance is still necessary. In this work, an asymmetric-dual-grating-gate graphene-terahertz-field-effect-transistor with a graphite back-gate was fabricated and characterized under illumination of 0.3 THz radiation in the temperature range from 4.5 K up to the room temperature. The device was fabricated as a sub-THz detector using a heterostructure of h-BN/Graphene/h-BN/Graphite to make a transistor with a double asymmetric-grating-top-gate and a continuous graphite back-gate. By biasing the metallic top-gates and the graphite back-gate, abrupt n+n (or p+p) or np (or pn) junctions with different potential barriers are formed along the graphene layer leading to enhancement of the THz rectified signal by about an order of magnitude. The plasmonic rectification for graphene containing np junctions is interpreted as due to the plasmonic electron-hole ratchet mechanism, whereas, for graphene with n+n junctions, rectification is attributed to the differential plasmonic drag effect. This work shows a new way of responsivity enhancement and paves the way towards new record performances of graphene THz nano-photodetectors.

【 授权许可】

Unknown