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arXiv · 2101.06447

Experimental Confirmation of Massive Dirac Fermions in Weak Charge-Ordering State in \alpha-(BEDT-TTF)_2I_3

Kenta Yoshimura·Mitsuyuki Sato·Toshihito Osada
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Abstract

The electronic structure of weak charge-ordering (CO) state just below the critical pressure in an organic conductor \alpha-(BEDT-TTF)_2I_3 was experimentally investigated using peak structure in the temperature dependence of interlayer magnetoresistance (MR). Based on a minimal model considering multiple Landau levels (LLs), we discuss herein the MR peak as characteristic to multilayer massless/massive Dirac fermion (DF) systems. MR measured in the weak CO state exhibited a clear MR peak, and its magnetic-field dependence was consistent with the LL behavior of a massive DF with a small gap. Results indicate that the weak CO state in \alpha-(BEDT-TTF)_2I_3 is a massive DF state.

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Kenta Yoshimura, Mitsuyuki Sato, Toshihito Osada. 2021-01-16. Experimental Confirmation of Massive Dirac Fermions in Weak Charge-Ordering State in \alpha-(BEDT-TTF)_2I_3. https://doi.org/10.7566/jpsj.90.033701

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