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arXiv · 2012.05449

Time-inhomogeneous Quantum Markov Chains with Decoherence on Finite State Spaces

Chia-Han Chou·Wei-Shih Yang
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Abstract

We introduce and study time-inhomogeneous quantum Markov chains with parameter $\zeta \ge 0$ and decoherence parameter $0 \leq p \leq 1$ on finite spaces and their large scale equilibrium properties. Here $\zeta$ resembles the inverse temperature in the annealing random process and $p$ is the decoherence strength of the quantum system. Numerical evaluations show that if $ \zeta$ is small, then quantum Markov chain is ergodic for all $0 < p \le 1$ and if $ \zeta $ is large, then it has multiple limiting distributions for all $0 < p \le 1$. In this paper, we prove the ergodic property in the high temperature region $0 \le \zeta \le 1$. We expect that the phase transition occurs at the critical point $\zeta_c=1$. For coherence case $p=0$, a critical behavior of periodicity also appears at critical point $\zeta_o=2$.

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Chia-Han Chou, Wei-Shih Yang. 2020-12-10. Time-inhomogeneous Quantum Markov Chains with Decoherence on Finite State Spaces. https://arxiv.org/abs/2012.05449

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