Abstract-Terahertz detection by epitaxial-graphene field-effect-transistors on silicon carbide

F. Bianco^1,a), D. Perenzoni², D. Convertino³, S. L. De Bonis^1,b), D. Spirito^1,c),M. Perenzoni², C. Coletti³, M. S. Vitiello¹ and A. Tredicucci^2,4
 HIDE AFFILIATIONS
1 NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, 56127 Pisa, Italy
2 Fondazione Bruno Kessler (FBK), Via Sommarive 18, 38123 Povo, Trento, Italy
3 CNI@NEST, Istituto Italiano di Tecnologia, Piazza S. Silvestro 12, 56127 Pisa, Italy
4 NEST, Istituto Nanoscienze-CNR and Dipartimento di Fisica “E. Fermi”, Università di Pisa, Largo Bruno Pontecorvo 3, 56127 Pisa, Italy
a) Author to whom correspondence should be addressed. Electronic mail: federicabianco82@gmail.com
b) Present address: ICFO, Av. Carl Friedrich Gauss, Centre d'Investigació en Nanociència, Castelldefels, Barcelona 08860, Spain.
c) Present address: Istituto Italiano di Tecnologia, Nanochemistry department and Graphene labs, Via Morego 30, 16163 Genova, Italy.
Appl. Phys. Lett. 107, 131104 (2015); http://dx.doi.org/10.1063/1.4932091

http://scitation.aip.org/content/aip/journal/apl/107/13/10.1063/1.4932091?TRACK=RSS

We report on room temperature detection of terahertz radiation by means of antenna-coupledfield effect transistors (FETs) fabricated using epitaxial graphene grown on silicon carbide. The achieved photoresponsivity (∼0.25 V/W) and noise equivalent power (∼80 nW/ Hz−−−√ ) result from the combined effect of two independent detection mechanisms: over-damped plasma wave rectification and thermoelectric effects, the latter ascribed to the presence of carrier density junctions along the FET channel. The calculated plasmonic and thermoelectric response reproduces qualitatively well the measured photovoltages; the experimentally observed sign-switch demonstrates the stronger contribution of plasmonic detection compared to the thermoelectric one. These results unveil the potential of plasmonic detectors exploitingepitaxial graphene on silicon carbide for fast large area imaging of macroscopic samples.