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arXiv · 0910.3737

Magnetoresistance in Single Layer Graphene: Weak Localization and Universal Conductance Fluctuation Studies

Yung-Fu Chen·Myung-Ho Bae·Cesar Chialvo·Travis Dirks·Alexey Bezryadin·Nadya Mason
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Abstract

We report measurements of magnetoresistance in single-layer graphene as a function of gate voltage (carrier density) at 250 mK. By examining signatures of weak localization (WL) and universal conductance fluctuations (UCF), we find a consistent picture of phase coherence loss due to electron-electron interactions. The gate-dependence of the elastic scattering terms suggests that the effect of trigonal warping, i.e., the non-linearity of the dispersion curves, may be strong at high carrier densities, while intra-valley scattering may dominate close to the Dirac point. In addition, a decrease in UCF amplitude with decreasing carrier density can be explained by a corresponding loss of phase coherence.

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Yung-Fu Chen, Myung-Ho Bae, Cesar Chialvo, Travis Dirks, Alexey Bezryadin, Nadya Mason. 2009-10-20. Magnetoresistance in Single Layer Graphene: Weak Localization and Universal Conductance Fluctuation Studies. https://doi.org/10.1088/0953-8984%2F22%2F20%2F205301

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