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arXiv · 2505.23636

Fischer Information of a Nonequilibrium Anharmonic Donor-Acceptor Rectifier

Bitap Raj Thakuria·Trishna Kalita·Javed Akhtar·Himangshu Prabal Goswami
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Abstract

We investigate a nonequilibrium donor-acceptor quantum rectifier system coupled to an anharmonic vibrational mode, treating the vibrational dynamics both as a two-level system and as multilevel system. The time-dependent Fischer information is then calculated by deriving a quantum master equation for the reduced system dynamics. We estimate some key rectifier parameters, the donor energy, the acceptor energy, and the vibrational frequency. We report that there is an optimal time for estimating the donor and acceptor energy. However, the anharmonic mode can be estimated better only in the steadystate. The acceptor energy is found to be most precisely estimable, especially under strong coupling and high bias. Donor energy shows limited sensitivity, while vibrational frequency estimation benefits from low temperatures. This work offers a theoretical foundation for enhancing parameter estimation in nanoscale quantum devices, guiding future sensing and metrological applications in quantronic systems.

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Bitap Raj Thakuria, Trishna Kalita, Javed Akhtar, Himangshu Prabal Goswami. 2025-05-29. Fischer Information of a Nonequilibrium Anharmonic Donor-Acceptor Rectifier. https://arxiv.org/abs/2505.23636

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