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Quantal interferometry with dissipative internal motion

Erik Sjöqvist
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Abstract

In presence of dissipation, quantal states may acquire complex-valued phase effects. We suggest a notion of dissipative interferometry that accommodates this complex-valued structure and that may serve as a tool for analyzing the effect of certain kinds of external influences on quantal interference. The concept of mixed-state phase and concomitant gauge invariance is extended to dissipative internal motion. The resulting complex-valued mixed-state interference effects lead to well-known results in the unitary limit and in the case of dissipative motion of pure quantal states. Dissipative interferometry is applied to fault-tolerant geometric quantum computation.

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Erik Sjöqvist. 2004-06-02. Quantal interferometry with dissipative internal motion. https://doi.org/10.1103/physreva.70.052109

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