Fast and Sensitive Terahertz Detection Using an Antenna-Integrated Graphene pn Junction
Castilla, Sebastián (Institut de Ciències Fotòniques)
Terrés, Bernat (Institut de Ciències Fotòniques)
Autore, Marta (CIC NanoGUNE)
Viti, Leonardo (Istituto Nanoscienze and Scuola Normale Superiore)
Li, Jian (Nanjing University)
Nikitin, Alexey Y. (IKERBASQUE)
Vangelidis, Ioannis (University of Ioannina. Department of Materials Science and Engineering)
Watanabe, Kenji (National Institute for Material Science (Tsukuba, Japan))
Taniguchi, Takashi (National Institute for Material Science (Tsukuba, Japan))
Lidorikis, Elefterios (University of Ioannina. Department of Materials Science and Engineering)
Vitiello, Miriam S. (Istituto Nanoscienze and Scuola Normale Superiore)
Hillenbrand, Rainer (IKERBASQUE)
Tielrooij, Klaas-Jan (Institut Català de Nanociència i Nanotecnologia)
Koppens, Frank (Institut de Ciències Fotòniques)

Data:	2019
Resum:	Although the detection of light at terahertz (THz) frequencies is important for a large range of applications, current detectors typically have several disadvantages in terms of sensitivity, speed, operating temperature, and spectral range. Here, we use graphene as a photoactive material to overcome all of these limitations in one device. We introduce a novel detector for terahertz radiation that exploits the photothermoelectric (PTE) effect, based on a design that employs a dual-gated, dipolar antenna with a gap of ?100 nm. This narrow-gap antenna simultaneously creates a pn junction in a graphene channel located above the antenna and strongly concentrates the incoming radiation at this pn junction, where the photoresponse is created. We demonstrate that this novel detector has an excellent sensitivity, with a noise-equivalent power of 80 pW/Hz at room temperature, a response time below 30 ns (setup-limited), a high dynamic range (linear power dependence over more than 3 orders of magnitude) and broadband operation (measured range 1. 8-4. 2 THz, antenna-limited), which fulfills a combination that is currently missing in the state-of-the-art detectors. Importantly, on the basis of the agreement we obtained between experiment, analytical model, and numerical simulations, we have reached a solid understanding of how the PTE effect gives rise to a THz-induced photoresponse, which is very valuable for further detector optimization.
Ajuts:	Ministerio de Economía y Competitividad SEV-2015-0522 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-1656 European Commission 785219 Ministerio de Economía y Competitividad SEV-2017-0706 Ministerio de Economía y Competitividad FIS2014-59639-JIN European Commission 681379 Ministerio de Economía y Competitividad MAT2017-88358-C3-3-R Ministerio de Economía y Competitividad MDM-2016-0618
Drets:	Tots els drets reservats.
Llengua:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Matèria:	Photodetector ; THz ; Graphene ; Antenna ; Pn junction ; Fast detection
Publicat a:	Nano letters, Vol. 19, Issue 5 (May 2019) , p. 2765-2773, ISSN 1530-6992

DOI: 10.1021/acs.nanolett.8b04171
PMID: 30882226

Postprint 27 p, 5.7 MB

El registre apareix a les col·leccions:
Documents de recerca > Documents dels grups de recerca de la UAB > Centres i grups de recerca (producció científica) > Ciències > Institut Català de Nanociència i Nanotecnologia (ICN2)
Articles > Articles de recerca
Articles > Articles publicats