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arXiv · 1903.07192

A limit distribution for a quantum walk driven by a five-diagonal unitary matrix

Takuya Machida
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Abstract

In this paper, we work on a quantum walk whose system is manipulated by a five-diagonal unitary matrix, and present long-time limit distributions. The quantum walk launches off a location and delocalizes in distribution as its system is getting updated. The five-diagonal matrix contains a phase term and the quantum walk becomes a standard coined walk when the phase term is fixed at special values. Or, the phase term gives an effect on the quantum walk. As a result, we will see an explicit form of a long-time limit distribution for a quantum walk driven by the matrix, and thanks to the exact form, we understand how the quantum walker approximately distributes in space after the long-time evolution has been executed on the walk.

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Takuya Machida. 2019-03-17. A limit distribution for a quantum walk driven by a five-diagonal unitary matrix. https://doi.org/10.26421/qic21.1-2-2

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