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arXiv · 2011.10060

Quantum-limit Hall effect with large carrier density in topological semimetals

Guang Yang·Yi Zhang
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Abstract

The quantum-limit Hall effect at $\nu = nh/eB\sim O(1)$ that hosts a variety of exotic quantum phenomena requires demanding strong magnetic field $B$ and low carrier density $n$. We propose to realize quantum-limit Hall effect even in the presence of large carrier density residues $n_e$ and $n_h$ relative to the magnetic field $B$ in topological semimetals, where a single Fermi surface contour allow both electron-type and hole-type carriers and approaches charge neutrality as $n_e\sim n_h$. The underlying filling factor $\nu = |n_e-n_h|h/eB$ explicitly violates the Onsager's relation for quantum oscillations.

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Guang Yang, Yi Zhang. 2020-11-19. Quantum-limit Hall effect with large carrier density in topological semimetals. https://doi.org/10.1103/physrevb.103.l241104

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