Skeleton structure inherent in discrete-time quantum walks
Tomoki Yamagami, Etsuo Segawa, Ken’ichiro Tanaka, Takatomo Mihana, André Röhm, Ryoichi Horisaki, Makoto Naruse · Physical Review A · 2023
In this paper we claim that a common underlying structure---a skeleton structure---is present behind discrete-time quantum walks (QWs) on a one-dimensional lattice with a homogeneous coin matrix. This skeleton structure is independent of the initial state, and partially, even of the coin matrix. This structure is best interpreted in the context of quantum-walk-replicating random walks (QWRWs), i.e., random walks that replicate the probability distribution of quantum walks, where this structure acts as a simplified formula for the transition probability. Additionally, we construct a random walk whose transition probabilities are defined by the skeleton structure and demonstrate that the resultant properties of the walkers are similar to both the original QWs and QWRWs.