TY - JOUR
T1 - Imaging coherent transport in a mesoscopic graphene ring
AU - Cabosart, Damien
AU - Faniel, Sébastien
AU - Martins, Frederico
AU - Brun, Boris
AU - Felten, Alexandre
AU - Bayot, Vincent
AU - Hackens, Benoit
PY - 2014/11/25
Y1 - 2014/11/25
N2 - Mesoscopic graphene devices often exhibit complex transport properties, stemming both from the peculiar electronic band structure of graphene and from the high sensitivity of transport to local disorder in this two-dimensional crystal. To disentangle contributions of disorder in the different transport phenomena at play in such devices, it is necessary to devise new local-probe methods and to establish links between transport and the microscopic structure of the devices. Here, we present a spatially resolved investigation of coherent transport inside a graphene quantum ring (QR), where Aharonov-Bohm conductance oscillations are observed. Thanks to scanning gate microscopy (SGM), we first identify spatial signatures of the Coulomb blockade, associated with disorder-induced localized states, and of charge-carrier interferences. We then image resonant states which decorate the QR local density of states (LDOS). Simulations of the LDOS in a model disorder graphene QR and temperature dependence of SGM maps confirm the presence of such scarred states.
AB - Mesoscopic graphene devices often exhibit complex transport properties, stemming both from the peculiar electronic band structure of graphene and from the high sensitivity of transport to local disorder in this two-dimensional crystal. To disentangle contributions of disorder in the different transport phenomena at play in such devices, it is necessary to devise new local-probe methods and to establish links between transport and the microscopic structure of the devices. Here, we present a spatially resolved investigation of coherent transport inside a graphene quantum ring (QR), where Aharonov-Bohm conductance oscillations are observed. Thanks to scanning gate microscopy (SGM), we first identify spatial signatures of the Coulomb blockade, associated with disorder-induced localized states, and of charge-carrier interferences. We then image resonant states which decorate the QR local density of states (LDOS). Simulations of the LDOS in a model disorder graphene QR and temperature dependence of SGM maps confirm the presence of such scarred states.
UR - http://www.scopus.com/inward/record.url?scp=84915747576&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.90.205433
DO - 10.1103/PhysRevB.90.205433
M3 - Article
AN - SCOPUS:84915747576
SN - 1098-0121
VL - 90
JO - Physical Review. B, Condensed Matter and Materials Physics
JF - Physical Review. B, Condensed Matter and Materials Physics
IS - 20
M1 - 205433
ER -