arXiv:1505.01248 · Physical Review A

Ramsauer effect in a one-dimensional quantum walk with multiple defects

Ho Tat Lam, Kwok Yip Szeto

Published Jul 20, 2015• 8 citations

Abstract

Experimental observations of quantum walks in one dimension have provided many exciting applications in quantum computing, while recent theoretical investigation of single-phase defect in these system points towards interesting phenomena associated with bound states. Here we obtain analytical solutions of a quantum walk with a general quantum coin in one dimension with multiple defects, with predictions on the condition for zero reflectance for scattering state and the existence of an analogy to the Ramsauer effect for multiple defects. We also show the transition from the zero-reflectance state to the bound state can provide a method for preparing the quantum walk in a bound state. Applications to systems similar to thin film optics are suggested.

DOI: 10.1103/physreva.92.012323

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