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arXiv · 2505.15711

Dissipative phase transition of interacting non-reciprocal fermions

Rafael D. Soares·Matteo Brunelli·Marco Schirò
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Abstract

While non-reciprocal couplings are ubiquitous in classical systems, their impact on quantum many-body criticality and entanglement remains largely unexplored. Using exact numerical simulations, we study an interacting fermionic chain subject to non-reciprocal gain and loss. We show that the interplay between dissipation and interactions drives a dissipative phase transition, marked by the opening of a many-body gap and a crossover from power-law to exponential relaxation. The weakly-interacting regime displays non-reciprocal signatures, including nonzero currents and directional charge accumulation reminiscent of the skin effect. Notably, despite this localization, quantum trajectories exhibit volume-law entanglement. Finally, reciprocity is dynamically restored above a critical interaction strength.

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Rafael D. Soares, Matteo Brunelli, Marco Schirò. 2025-05-21. Dissipative phase transition of interacting non-reciprocal fermions. https://doi.org/10.1103/n8xv-kygx

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