{ "id": "2105.14270", "version": "v1", "published": "2021-05-29T11:09:54.000Z", "updated": "2021-05-29T11:09:54.000Z", "title": "A discontinuity of the energy of quantum walk in impurities", "authors": [ "Kenta Higuchi", "Takashi Komatsu", "Norio Konno", "Hisashi Morioka", "Etsuo Segawa" ], "comment": "16 pages. arXiv admin note: text overlap with arXiv:1912.11555", "categories": [ "math-ph", "math.MP" ], "abstract": "We consider the discrete-time quantum walk whose local dynamics is denoted by $C$ at the perturbed region $\\{0,1,\\dots,M-1\\}$ and free at the other positions. We obtain the stationary state with a bounded initial state. The initial state is set so that the perturbed region receives the inflow $\\omega^n$ at time $n$ $(|\\omega|=1)$. From this expression, we compute the scattering on the surface of $-1$ and $M$ and also compute the quantity how quantum walker accumulates in the perturbed region; namely the energy of the quantum walk, in the long time limit. We find a discontinuity of the energy with respect to the frequency of the inflow.", "revisions": [ { "version": "v1", "updated": "2021-05-29T11:09:54.000Z" } ], "analyses": { "keywords": [ "discontinuity", "impurities", "discrete-time quantum walk", "quantum walker accumulates", "long time limit" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable" } } }