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arXiv · 2010.13329

Enhancements of the 3/2 and 5/2 frequencies of de Haas-van Alphen oscillations near the Lifshitz transition in the two-dimensional compensated metal with overtilted Dirac cones

Keita Kishigi·Yasumasa Hasegawa
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Abstract

We study the de Haas-van Alphen (dHvA) oscillations in the two-dimensional compensated metal with overtilted Dirac cones near the Lifshitz transition. We employ the tight-binding model of $α$-(BEDT-TTF)$_2$I$_3$, in which the massless Dirac fermions are realized. When a uniaxial pressure $(P)$ along the $y$-axis is applied above $P\simeq 0.2$ kbar in $α$-(BEDT-TTF)$_2$I$_3$, one electron pocket, which encloses the overtilted Dirac points, is changed to two electron pockets, i.e., Lifshitz transition happens, while a hole pocket does not change a topology. We show that the Fourier components corresponding to the $3/2$ and $5/2$ areas of the hole pocket are anomalously enhanced in the region of pressure where the Lifshitz transition occurs. This phenomenon will be observed in the two-dimensional overtilted Dirac fermions near the Lifshitz transition.

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Keita Kishigi, Yasumasa Hasegawa. 2020-10-26. Enhancements of the 3/2 and 5/2 frequencies of de Haas-van Alphen oscillations near the Lifshitz transition in the two-dimensional compensated metal with overtilted Dirac cones. https://doi.org/10.1103/physrevb.100.195433

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