35 citations · 217 across the 32 of their papers we have counts for
33 papers
Eigenvalues and threshold rezonances of a two-dimensional split-step quantum walk with strong shift
Toru Fuda, Daiju Funakawa, Satoshi Sasayama +1
In this paper, we derive sufficient conditions for the localization of two-dimensional split-step quantum walks with a strong shift. For this purpose, we analyze the zero points of…
Spectral mapping theorem of an abstract non-unitary quantum walk
Keisuke Asahara, Daiju Funakawa, Etsuo Segawa +2
This paper continues the previous work (Quantum Inf. Process (2019)) by two authors of the present paper about a spectral mapping property of chiral symmetric unitary operators. In…
The Witten index for one-dimensional split-step quantum walks under the non-Fredholm condition
Yasumichi Matsuzawa, Akito Suzuki, Yohei Tanaka +2
It is recently shown that a split-step quantum walk possesses a chiral symmetry, and that a certain well-defined index can be naturally assigned to it. The index is a well-defined…
Spectral analysis for a multi-dimensional split-step quantum walk with a defect
Toru Fuda, Akihiro Narimatsu, Kei Saito +1
This paper studies the spectrum of a multi-dimensional split-step quantum walk with a defect that cannot be analysed in the previous papers. To this end, we have developed a new te…
Absence of singular continuous spectra and embedded eigenvalues for one dimensional quantum walks with general long-range coins
Masaya Maeda, Akito Suzuki, Kazuyuki Wada
This paper is a continuation of the paper \cite{W} by the third author, which studied quantum walks with special long-range perturbations of the coin operator. In this paper, we co…
The Witten Index for 1D Supersymmetric Quantum Walks with Anisotropic Coins
Akito Suzuki, Yohei Tanaka
Chirally symmetric discrete-time quantum walks possess supersymmetry, and their Witten indices can be naturally defined. The Witten index gives a lower bound for the number of topo…