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arXiv · 2010.09160

Universal Behavior of Magnetoresistance in Organic Dirac Electron Systems

Ryotaro Kobara·Shin Igarashi·Yoshitaka Kawasugi·Ryusei Doi·Toshio Naito·Masafumi Tamura·Reizo Kato·Yutaka Nishio·Koji Kajita·Naoya Tajima
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Abstract

In-plane magnetoresistance for organic massless Dirac electron system (OMDES) $\alpha$-(BEDT-TTF)$_2$I$_3$ and $\theta$-(BEDT-TTF)$_2$I$_3$ in addition to possible candidates of the OMDES $\alpha$-(BETS)$_2$I$_3$ and $\alpha$-(BEDT-STF)$_2$I$_3$, was investigated under hydrostatic pressure. We have found the universal behavior of the in-plane magnetoresistance under a low magnetic field perpendicular to two-dimensional plane. As for $\alpha$-(BEDT-TTF)$_2$I$_3$, the universality was examined with the parameters of temperature, magnetic field and its direction. We suggest that the universal magnetoresistance behavior is found even for the gapped state of $\alpha$-(BEDT-TTF)$_2$I$_3$ under intermediate pressure, when the thermal energy exceeds the gap.

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Ryotaro Kobara, Shin Igarashi, Yoshitaka Kawasugi, Ryusei Doi, Toshio Naito, Masafumi Tamura, Reizo Kato, Yutaka Nishio, Koji Kajita, Naoya Tajima. 2020-10-19. Universal Behavior of Magnetoresistance in Organic Dirac Electron Systems. https://doi.org/10.7566/jpsj.89.113703

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