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arXiv · 1602.07005

Insulating nature of strongly correlated massless Dirac fermions in an organic crystal

Dong Liu·Kyohei Ishikawa·Ryosuke Takehara·Kazuya Miyagawa·Masafumi Tamura·Kazushi Kanoda
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Abstract

Through resistivity measurements of an organic crystal hosting massless Dirac fermions with a charge-ordering instability, we reveal the effect of interactions among Dirac fermions on the charge transport. A low-temperature resistivity upturn appears robustly irrespectively of pressure and is enhanced while approaching the critical pressure of charge ordering, indicating that the insulating behavior originates from short-range Coulomb interactions. Observation of apparently vanishing gap in the charge-ordered phase accords with the theoretical prediction of the non-topological edge states.

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Dong Liu, Kyohei Ishikawa, Ryosuke Takehara, Kazuya Miyagawa, Masafumi Tamura, Kazushi Kanoda. 2016-02-23. Insulating nature of strongly correlated massless Dirac fermions in an organic crystal. https://doi.org/10.1103/physrevlett.116.226401

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