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arXiv · 2512.00816

Helical Edge Transport in the \nu = 0 Quantum Hall Ferromagnetic State of an Organic Dirac Fermion System

Toshihito Osada·Mitsuyuki Sato·Takako Konoike·Woun Kang
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Abstract

We experimentally confirm the \nu = 0 quantum Hall ferromagnetic (QHF) state, accompanied by helical edge states, in the layered organic Dirac-fermion system \alpha-(ET)2I3 by demonstrating helical edge transport in multilayers. The saturation of interlayer magnetoresistance (MR) in the high-magnetic-field quantum limit does not scale with the sample cross-sectional area and appears when the magnetic field is oriented along the side surface. The in-plane MR exhibits a similar angle dependence, whereas this feature disappears in the Corbino geometry where no edge channels are present. These results are consistent with helical edge transport in the multilayer QHF state. They also rule out the possibility that the observed angle-dependent MR arises from the chiral magnetic effect expected for a 3D Dirac or Weyl semimetal.

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Toshihito Osada, Mitsuyuki Sato, Takako Konoike, Woun Kang. 2025-11-30. Helical Edge Transport in the \nu = 0 Quantum Hall Ferromagnetic State of an Organic Dirac Fermion System. https://doi.org/10.56646/jjapcp.12.0_011013

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