%0 Journal Article
%T A corner reflector of graphene Dirac fermions as a phonon-scattering sensor
%+ Physique Mésoscopique
%+ Laboratoire de physique de l'ENS - ENS Paris (LPENS (UMR_8023))
%+ KEK (High energy accelerator research organization)
%+ National Institute for Fusion Science (NIFS)
%A Graef, H.
%A Wilmart, Q.
%A Rosticher, M.
%A Mele, D.
%A Banszerus, L.
%A Stampfer, C.
%A Taniguchi, T.
%A Watanabe, K.
%A Berroir, Jean-Marc
%A Bocquillon, Erwann
%A Fève, G.
%A Teo, E, H T
%A Plaçais, Bernard
%< avec comité de lecture
%@ 2041-1723
%J Nature Communications
%I Nature Publishing Group
%V 10
%N 1
%P 2428
%8 2019-12
%D 2019
%R 10.1038/s41467-019-10326-6
%K Nanoscience and technology
%K Physics
%Z Physics [physics]/Physics [physics]/Optics [physics.optics]
%Z Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall]Journal articles
%X Dirac fermion optics exploits the refraction of chiral fermions across optics-inspired Klein-tunneling barriers defined by high-transparency p-n junctions. We consider the corner reflector (CR) geometry introduced in optics or radars. We fabricate Dirac fermion CRs using bottom-gate-defined barriers in hBN-encapsulated graphene. By suppressing transmission upon multiple internal reflections, CRs are sensitive to minute phonon scattering rates. Here we report on doping-independent CR transmission in quantitative agreement with a simple scattering model including thermal phonon scattering. As a signature of CRs, we observe Fabry-Pérot oscillations at low temperature, consistent with single-path reflections. Finally, we demonstrate high-frequency operation which promotes CRs as fast phonon detectors. Our work establishes the relevance of Dirac fermion optics in graphene and opens a route for its implementation in topological Dirac matter.
%G English
%2 https://hal.sorbonne-universite.fr/hal-02159529/document
%2 https://hal.sorbonne-universite.fr/hal-02159529/file/s41467-019-10326-6.pdf
%L hal-02159529
%U https://hal.sorbonne-universite.fr/hal-02159529
%~ UNIV-PARIS7
%~ ENS-PARIS
%~ CNRS
%~ OPENAIRE
%~ PSL
%~ USPC
%~ SORBONNE-UNIVERSITE
%~ SORBONNE-UNIV
%~ SU-SCIENCES
%~ SU-SCI
%~ LPENS
%~ UNIV-PARIS
%~ UP-SCIENCES
%~ ENS-PSL
%~ SU-TI
%~ ANR
%~ ALLIANCE-SU