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arXiv · 2510.19317

Decoherence of a dissipative Brownian charged magneto-anharmonic oscillator: an information theoretic approach

Suraka Bhattacharjee·Koushik Mandal·Supurna Sinha
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Abstract

We study the decoherence of an anisotropic anharmonic oscillator in a magnetic field, coupled to a bath of harmonic oscillators at high and low temperatures. We solve the anharmonic oscillator problem using perturbative techniques and derive the non-Markovian master equation in the weak coupling limit. The anharmonicity parameter {\alpha} enhances decoherence due to the deconfining effect of anharmonicity. The oscillatory nature of the time evolution of heating function indicates information backflow. The von-Neumann entropy is also calculated for the system, which increases with {\alpha}, consistent with the deconfining effect noted in the decoherence analysis. We have also proposed a cold ion experimental set up for testing our theoretical predictions. The study is of relevance to the domain of quantum technology where decoherence significantly affects the performance of a quantum computer.

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Suraka Bhattacharjee, Koushik Mandal, Supurna Sinha. 2025-10-22. Decoherence of a dissipative Brownian charged magneto-anharmonic oscillator: an information theoretic approach. https://arxiv.org/abs/2510.19317

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