Keisuke Asahara, Daiju Funakawa, Etsuo Segawa, Akito Suzuki, Noriaki Teranishi. Spectral mapping theorem of an abstract non-unitary quantum walk. Linear Algebra and its Applications. 2023. 676. 1-24
Toru Fuda, Daiju Funakawa, Satoshi Sasayama, Akito Suzuki. Eigenvalues and threshold resonances of a two-dimensional split-step quantum walk with strong shift. Quantum Studies: Mathematics and Foundations. 2023
Keisuke Asahara, Daiju Funakawa, Motoki Seki, Yohei Tanaka. An index theorem for one-dimensional gapless non-unitary quantum walks. Quantum Information Processing. 2021. 20. 9
Keisuke ASAHARA, Daiju FUNAKAWA. Spectral analysis of an abstract pair interaction model. Hokkaido Mathematical Journal. 2021. 50. 1
Daiju Funakawa, Yasumichi Matsuzawa, Itaru Sasaki, Akito Suzuki, Noriaki Teranishi. Time operators for quantum walks. Letters in Mathematical Physics. 2020. 110. 9. 2471-2490