Feynman Integral in Quantum Walk, Barrier-top Scattering and Hadamard Walk
@inproceedings{Higuchi2021FeynmanII, title={Feynman Integral in Quantum Walk, Barrier-top Scattering and Hadamard Walk}, author={Ken Higuchi}, year={2021} }
The aim of this article is to relate the discrete quantum walk on Z with the continuous Schrödinger operator on R in the scattering problem. Each point of Z is associated with a barrier of the potential, and the coin operator of the quantum walk is determined by the transfer matrix between bases of WKB solutions on the classically allowed regions of both sides of the barrier. This correspondence enables us to represent each entry of the scattering matrix of the Schrödinger operator as a…
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