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arXiv · 1802.04904

The Structure of Decoherence-free Subsystems

Ji Guan·Yuan Feng·Mingsheng Ying
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Abstract

Decoherence-free subsystems have been successfully developed as a tool to preserve fragile quantum information against noises. In this letter, we develop a structure theory for decoherence-free subsystems. Based on it, we present an effective algorithm to construct a set of maximal decoherence-free subsystems in the sense that any other such subsystem is a subspace of one of them. As an application of these techniques in quantum many body systems, we propose a simple and numerically robust method to determine if two irreducible tensors are repeated, a key step in deciding if they are equivalent in generating matrix product states.

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Ji Guan, Yuan Feng, Mingsheng Ying. 2018-02-14. The Structure of Decoherence-free Subsystems. https://arxiv.org/abs/1802.04904

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