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arXiv · 1901.10665

Time operators for continuous-time and discrete-time quantum walks

Daiju Funakawa·Yasumichi Matsuzawa·Akito Suzuki·Itaru Sasaki·Noriaki Teranishi
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Abstract

We construct concrete examples of time operators for both continuous and discrete-time homogeneous quantum walks, and we determine their deficiency indices and spectra. For a discrete-time quantum walk, the time operator can be self-adjoint if the time evolution operator has a non-zero winding number. In this case, its spectrum becomes a discrete set of real numbers.

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Daiju Funakawa, Yasumichi Matsuzawa, Akito Suzuki, Itaru Sasaki, Noriaki Teranishi. 2020-06-22. Time operators for continuous-time and discrete-time quantum walks. https://arxiv.org/abs/1901.10665

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