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arXiv · 2311.13918

Effect of dephasing on the current through a periodically driven quantum point contact

Igor Ermakov·Oleg Lychkovskiy
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Abstract

We consider two one-dimensional quantum $XX$ magnets linked by a periodically driven quantum point contact (QPC). If magnets are initially polarized in opposite directions, one expects that a spin current through the QPC will establish. It has been shown recently [Phys. Rev. B 103, L041405 (2021)] that, in fact, when the driving frequency exceeds a critical value, the current halts completely, the QPC being effectively insulating. Here we enquire how this picture is affected by quantum dephasing. Our findings reveal that any non-zero dephasing restores the current.

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Igor Ermakov, Oleg Lychkovskiy. 2023-11-23. Effect of dephasing on the current through a periodically driven quantum point contact. https://doi.org/10.1134/s0021364023603299

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