TY - JOUR
T1 - Ballistic interferences in suspended graphene
AU - Rickhaus, Peter
AU - Maurand, Romain
AU - Liu, Ming Hao
AU - Weiss, Markus
AU - Richter, Klaus
AU - Schönenberger, Christian
N1 - Funding Information:
We thank Alexander van der Torren and Dominik Bischoff for helping us to develop the graphene transfer method. M.-H.L. was supported by Alexander von Humboldt foundation. He and K.R. acknowledge the financial support of Deutsche For-schungsgemeinschaft (SFB 689). This work was financed by the Swiss NSF, the ESF programme Eurographene, the EU FP7 project SE2ND, the ERC Advanced Investigator Grant QUEST, the Swiss NCCR Nano and QSIT.
PY - 2013
Y1 - 2013
N2 - The low-energy electronic excitations in graphene are described by massless Dirac fermions that have a linear dispersion relation. Taking advantage of this 'optics-like' electron dynamics, generic optical elements like lenses and wave guides have been proposed for electrons in graphene. Tuning of these elements relies on the ability to adjust the carrier concentration in defined areas. However, the combination of ballistic transport and complex gating remains challenging. Here we report on the fabrication and characterization of suspended graphene p-n junctions. By local gating, resonant cavities can be defined, leading to complex Fabry-Pérot interferences. The observed conductance oscillations account for quantum interference of electrons propagating ballistically over distances exceeding 1 μm. Visibility of the interferences is demonstrated to be enhanced by Klein collimation at the p-n interface. This finding paves the way to more complex gate-controlled ballistic graphene devices and brings electron optics in graphene closer to reality.
AB - The low-energy electronic excitations in graphene are described by massless Dirac fermions that have a linear dispersion relation. Taking advantage of this 'optics-like' electron dynamics, generic optical elements like lenses and wave guides have been proposed for electrons in graphene. Tuning of these elements relies on the ability to adjust the carrier concentration in defined areas. However, the combination of ballistic transport and complex gating remains challenging. Here we report on the fabrication and characterization of suspended graphene p-n junctions. By local gating, resonant cavities can be defined, leading to complex Fabry-Pérot interferences. The observed conductance oscillations account for quantum interference of electrons propagating ballistically over distances exceeding 1 μm. Visibility of the interferences is demonstrated to be enhanced by Klein collimation at the p-n interface. This finding paves the way to more complex gate-controlled ballistic graphene devices and brings electron optics in graphene closer to reality.
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U2 - 10.1038/ncomms3342
DO - 10.1038/ncomms3342
M3 - Article
C2 - 23946010
AN - SCOPUS:84883121253
SN - 2041-1723
VL - 4
JO - Nature communications
JF - Nature communications
M1 - 2342
ER -