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Evolution operators for quantum chains

S. M. Sergeev
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Abstract

Discrete-time evolution operators in integrable quantum lattice models are sometimes more fundamental objects then Hamiltonians. In this paper we study an evolution operator for the one-dimensional integrable q-deformed Bose gas with XXZ-type impurities and find its spectrum. Evolution operators give a new interpretation of known integrable systems, for instance our system describes apparently a simplest laser with a clear resonance peak in the spectrum.

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S. M. Sergeev. 2006-07-25. Evolution operators for quantum chains. https://arxiv.org/abs/nlin/0607055

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