TY  - JOUR
A1  - Tan, Z. B.
A1  - Elo, T.
A1  - Puska, A.
A1  - Sarkar, J.
A1  - Lähteenmäki, P.
A1  - Duerr, F.
A1  - Gould, C.
A1  - Molenkamp, L. W.
A1  - Nagaev, K. E.
A1  - Hakonen, P. J.
T1  - Hanbury-Brown and Twiss exchange and non-equilibrium-induced correlations in disordered, four-terminal graphene-ribbon conductor
JF  - Scientific Reports
N2  - We have investigated current-current correlations in a cross-shaped conductor made of graphene. The mean free path of charge carriers is on the order of the ribbon width which leads to a hybrid conductor where there is diffusive transport in the device arms while the central connection region displays near ballistic transport. Our data on auto and cross correlations deviate from the predictions of Landauer-Büttiker theory, and agreement can be obtained only by taking into account contributions from non-thermal electron distributions at the inlets to the semiballistic center, in which the partition noise becomes strongly modified. The experimental results display distinct Hanbury – Brown and Twiss (HBT) exchange correlations, the strength of which is boosted by the non-equilibrium occupation-number fluctuations internal to this hybrid conductor. Our work demonstrates that variation in electron coherence along atomically-thin, two-dimensional conductors has significant implications on their noise and cross correlation properties.
KW  - conductive hybrid
KW  - partition noise
KW  - occupation number fluctuations
KW  - current-current correlation
KW  - device arm
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-240348
VL  - 8
ER  -