17 citations · 40 across the 23 of their papers we have counts for
10 papers · 1 filter
Mutually orthogonal Sudoku Latin squares and their graphs
Sho Kubota, Sho Suda, Akane Urano
We introduce a graph attached to mutually orthogonal Sudoku Latin squares. The spectra of the graphs obtained from finite fields are explicitly determined. As a corollary, we then…
Periodicity of Grover walks on bipartite regular graphs with at most five distinct eigenvalues
Sho Kubota
We determine connected bipartite regular graphs with four distinct adjacency eigenvalues that induce periodic Grover walks, and show that it is only . We also show that there…
One-dimensional optimal control problems for time-discrete constrained quasilinear diffusion equations of Allen--Cahn types
Shodai Kubota
In this paper, we consider a class of optimal control problems for a one-dimensional time-discrete constrained quasilinear diffusion state-systems of singular Allen--Cahn types and…
Perfect state transfer in Grover walks between states associated to vertices of a graph
Sho Kubota, Etsuo Segawa
We study perfect state transfer in Grover walks, which are typical discrete-time quantum walk models. In particular, we focus on states associated to vertices of a graph. We call s…
Temperature Control of PDE Constrained Optimization Problems Governed by Kobayashi--Warren--Carter Type Models of Grain Boundary Motions
Harbir Antil, Shodai Kubota, Ken Shirakawa +1
In this paper, we consider a class of optimal control problems governed by state-equations of Kobayashi--Warren--Carter type. The control is given by physical temperature. The focu…
Combinatorial necessary conditions for regular graphs to induce periodic quantum walks
Sho Kubota
We derive combinatorial necessary conditions for discrete-time quantum walks defined by regular mixed graphs to be periodic. If the quantum walk is periodic, all the eigenvalues of…
The trace formula with respect to the twisted Grover matrix of a mixed digraph
Takashi Komatsu, Sho Kubota, Norio Konno +1
We define a zeta function woth respect to the twisted Grover matrix of a mixed digraph, and present an exponential expression and a determinant expression of this zeta function. As…
Subdifferential decomposition of 1D-regularized total variation with nonhomogeneous coefficients
Shodai Kubota
In this paper, we consider a convex function defined as a 1D-regularized total variation with nonhomogeneous coefficients, and prove the Main Theorem concerned with the decompositi…
Periodicity of quantum walks defined by mixed paths and mixed cycles
Sho Kubota, Hiroto Sekido, Harunobu Yata
In this paper, we determine periodicity of quantum walks defined by mixed paths and mixed cycles. By the spectral mapping theorem of quantum walks, consideration of periodicity is…
A new type of spectral mapping theorem for quantum walks with a moving shift on graphs
Sho Kubota, Kei Saito, Yusuke Yoshie
The conventional spectral mapping theorem for quantum walks can only be applied for walks employing a shift operator whose square is the identity. This theorem gives most of the ei…