Quasi-isotropic orbital magnetoresistance in lightly doped SrTiO$_{3}$

Clément Collignon; Yudai Awashima; Ravi; Xiao Lin; Carl Willem Rischau; Anissa Acheche; Baptiste Vignolle; Cyril Proust; Yuki Fuseya; Kamran Behnia; Benoît Fauqué

doi:10.1103/physrevmaterials.5.065002

arXiv · 2101.09062

Quasi-isotropic orbital magnetoresistance in lightly doped SrTiO$_{3}$

Clément Collignon·Yudai Awashima·Ravi·Xiao Lin·Carl Willem Rischau·Anissa Acheche·Baptiste Vignolle·Cyril Proust·Yuki Fuseya·Kamran Behnia·Benoît Fauqué

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Abstract

A magnetic field parallel to an electrical current does not produce a Lorentz force on the charge carriers. Therefore, orbital longitudinal magnetoresistance is unexpected. Here we report on the observation of a large and non saturating magnetoresistance in lightly doped SrTiO$_{3-x}$ independent of the relative orientation of current and magnetic field. We show that this quasi-isotropic magnetoresistance can be explained if the carrier mobility along all orientations smoothly decreases with magnetic field. This anomalous regime is restricted to low concentrations when the dipolar correlation length is longer than the distance between carriers. We identify cyclotron motion of electrons in a potential landscape tailored by polar domains as the cradle of quasi-isotropic orbital magnetoresistance. The result emerges as a challenge to theory and may be a generic feature of lightly-doped quantum paralectric materials.

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Clément Collignon, Yudai Awashima, Ravi, Xiao Lin, Carl Willem Rischau, Anissa Acheche, Baptiste Vignolle, Cyril Proust, Yuki Fuseya, Kamran Behnia, Benoît Fauqué. 2021-01-22. Quasi-isotropic orbital magnetoresistance in lightly doped SrTiO$_{3}$. https://doi.org/10.1103/physrevmaterials.5.065002

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