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arXiv · 1910.03223

Longitudinal and transverse magnetoresistance of SrTiO$_3$ with a single closed Fermi surface

Yudai Awashima·Yuki Fuseya
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Abstract

The magnetoresistance (MR) of SrTiO$_3$ is theoretically investigated based on the Boltzmann equation by considering its detailed band structure. The formula for MR proposed by Mackey and Sybert is extended to be applicable to a system with an arbitrarily shaped Fermi surface. It is shown that the angular dependence of the diagonal component of the mass tensor causes transverse MR, whereas that of the off-diagonal component causes longitudinal MR with only a single closed Fermi surface, which overturns the textbook understanding of MR. The calculated MR (300% at 10 T) quantitatively agrees with the experimental results for SrTiO$_3$ including the behavior of the linear MR. The negative Gaussian curvature of the Fermi surface of SrTiO$_3$ and its resulting negative longitudinal and transverse MR are also discussed.

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Yudai Awashima, Yuki Fuseya. 2019-10-08. Longitudinal and transverse magnetoresistance of SrTiO$_3$ with a single closed Fermi surface. https://doi.org/10.1088/1361-648x%2Fab1b05

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