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arXiv · 1702.01087

Phonon-drag magnetoquantum oscillations in graphene

S. S. Kubakaddi·Tutul Biswas·Tarun Kanti Ghosh
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Abstract

A theory of low-temperature phonon-drag magnetothermopower $S_{xx}^g$ is presented in graphene in a quantizing magnetic field. $S_{xx}^g$ is found to exhibit quantum oscillations as a function of magnetic field $B$ and electron concentration $n_e$. Amplitude of the oscillations is found to increase (decrease) with increasing $B$ ($n_e$). The behavior of $S_{xx}^g$ is also investigated as a function of temperature. A large value of $S_{xx}^g $($\sim$ few hundreds of $μ$V/K) is predicted. Numerical values of $S_{xx}^g $ are compared with the measured magnetothermopower $S_{xx}$ and the diffusion component $S_{xx}^d$ from the modified Girvin-Jonson theory.

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S. S. Kubakaddi, Tutul Biswas, Tarun Kanti Ghosh. 2017-05-09. Phonon-drag magnetoquantum oscillations in graphene. https://doi.org/10.1088/1361-648x%2Faa749c

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