Parity-Selective Quantum Interference in Unconventional Magnets

Yiyuan Chen; Xiao-Bin Qiang; Hai-Zhou Lu; Congjun Wu; X. C. Xie

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arXiv · 2611.07330

Parity-Selective Quantum Interference in Unconventional Magnets

Yiyuan Chen·Xiao-Bin Qiang·Hai-Zhou Lu·Congjun Wu·X. C. Xie

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Abstract

Nonrelativistic spin splitting has emerged as a defining feature of unconventional magnetic states. Here we show that quantum interference offers a symmetry-resolved probe for the parity of such spin splitting, as even- and odd-parity magnets exhibit qualitatively different weak (anti-)localization behaviors. Even-parity magnets can host time-reversal symmetric scattering loops depicted by the spin group, giving rise to a weak localization that can be suppressed by spin-orbit coupling. In contrast, odd-parity magnets have a hidden weak antilocalization that can be released by spinorbit coupling. We further derive the corresponding magnetoconductivity formulas to facilitate experimental explorations. Our results not only advance the weak (anti-)localization theory to unconventional magnets but also suggest a practical diagnostic of unconventional spin-split magnetic states.

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Yiyuan Chen, Xiao-Bin Qiang, Hai-Zhou Lu, Congjun Wu, X. C. Xie. 2026-11-05. Parity-Selective Quantum Interference in Unconventional Magnets. https://arxiv.org/abs/2611.07330

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