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arXiv · 2508.19519

Current-Driven Symmetry Breaking and Spin-Orbit Polarization in Chiral Wires

Uiseok Jeong·Daniel Hill·Esmaeil Taghizadeh Sisakht·Binghai Yan·Angel Rubio·Carsten A. Ullrich·Noejung Park
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Abstract

The spin dynamics of electrons in chiral molecular systems remain a topic of intense interest, particularly regarding whether geometric chirality inherently induces spin polarization in current-carrying electrons. In this work, we employ ab initio real-time time-dependent density functional theory (rt-TDDFT) to directly simulate the interplay between charge current, spin, and orbital. This real-time tracking extends beyond perturbative treatments, and we analyze how nonequilibrium currents effectively lift the symmetry constraints of screw rotation and time-reversal symmetry. We find that the emergence of spin and orbital angular momenta is dynamically correlated with a concomitant loss of translational (linear) momentum, which we interpret as an intrinsic consequence of current-driven symmetry lowering. The implications of this mechanism for chirality-induced spin selectivity and spintronic device design are discussed.

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Uiseok Jeong, Daniel Hill, Esmaeil Taghizadeh Sisakht, Binghai Yan, Angel Rubio, Carsten A. Ullrich, Noejung Park. 2025-08-27. Current-Driven Symmetry Breaking and Spin-Orbit Polarization in Chiral Wires. https://arxiv.org/abs/2508.19519

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