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arXiv · 2005.12859

Fast charging of quantum battery assisted by noise

Srijon Ghosh·Titas Chanda·Shiladitya Mal·Aditi Sen De
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Abstract

We investigate the performance of a quantum battery exposed to local Markovian and non-Markovian dephasing noises. The battery is initially prepared as the ground state of a one-dimensional transverse $XY$ model with open boundary condition and is charged (discharged) via interactions with local bosonic reservoirs. We show that in the transient regime, quantum battery (QB) can store energy faster and has a higher maximum extractable work, quantified via ergotropy, when it is affected by local phase-flip or bit-flip Markovian noise compared to the case when there is no noise in the system. In both the charging and discharging processes, we report the enhancement in work-output as well as in ergotropy when all the spins are affected by non-Markovian Ohmic bath both in the transient and the steady-state regimes, thereby showing a counter-intuitive advantage of decoherence in QB. Both in Markovian and non-Markovian cases, we identify the system parameters and the corresponding noise models which lead to maximum enhancement of work-output and ergotropy. Moreover, we show that the benefit due to noise persists even with the initial state being prepared at a moderate temperature.

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Srijon Ghosh, Titas Chanda, Shiladitya Mal, Aditi Sen De. 2020-05-26. Fast charging of quantum battery assisted by noise. https://doi.org/10.1103/physreva.104.032207

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