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arXiv · 2103.10575

The localization of quantum random walks on sierpinski gaskets

Kai Zhao·Wei-Shih Yang
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Abstract

We consider the discrete time quantum random walks on a Sierpinski gasket. We study the hitting probability as the level of fractal goes to infinity in terms of their localization exponents $β_w$ , total variation exponents $δ_w$ and relative entropy exponents $η_w$ . We define and solve the amplitude Green functions recursively when the level of the fractal graph goes to infinity. We obtain exact recursive formulas for the amplitude Green functions, based on which the hitting probabilities and expectation of the first-passage time are calculated. Using the recursive formula with the aid of Monte Carlo integration, we evaluate their numerical values. We also show that when the level of the fractal graph goes to infinity, with probability 1, the quantum random walks will return to origin, i.e., the quantum walks on Sierpinski gasket are recurrent.

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Kai Zhao, Wei-Shih Yang. 2021-03-19. The localization of quantum random walks on sierpinski gaskets. https://doi.org/10.1063/5.0051324

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