Zobrazeno 1 - 10
of 54
pro vyhledávání: '"Higuchi, Kenta"'
Autor:
Higuchi, Kenta
Publikováno v:
Comptes Rendus. Mathématique, Vol 359, Iss 6, Pp 657-663 (2021)
We consider a $2\times 2$ system of one-dimensional semiclassical Schrödinger operators with small interactions with respect to the semiclassical parameter $h$. We study the asymptotics in the semiclassical limit of the resonances near a non-trappin
Externí odkaz:
https://doaj.org/article/fdacb03335f8450aa9d6d0e866251e4d
Autor:
Higuchi, Kenta, Watanabe, Takuya
In this paper, the asymptotic behaviors of the transition probability for two-level avoided crossings are studied under the limit where two parameters (adiabatic parameter and energy gap parameter) tend to zero. This is a continuation of our previous
Externí odkaz:
http://arxiv.org/abs/2404.17777
We consider a 1D $2\times 2$ matrix-valued operator \eqref{System0} with two semiclassical Schr\"odinger operators on the diagonal entries and small interactions on the off-diagonal ones. When the two potentials cross at a turning point with contact
Externí odkaz:
http://arxiv.org/abs/2402.19219
Autor:
Higuchi, Kenta, Morioka, Hisashi
In this paper, some properties of resonances for multi-dimensional quantum walks are studied. Resonances for quantum walks are defined as eigenvalues of complex translated time evolution operators in the pseudo momentum space. For some typical cases,
Externí odkaz:
http://arxiv.org/abs/2307.00962
Autor:
Higuchi, Kenta
A Landau-Zener type formula for a degenerate avoided-crossing is studied in the non-coupled regime. More precisely, a $2\times2$ system of first order $h$-differential operator with $\mathcal{O}(\varepsilon)$ off-diagonal part is considered in 1D. As
Externí odkaz:
http://arxiv.org/abs/2306.15465
In this paper, resonances are introduced to a class of quantum walks on $\mathbb{Z}$. Resonances are defined as poles of the meromorphically extended resolvent of the unitary time evolution operator. In particular, they appear inside the unit circle.
Externí odkaz:
http://arxiv.org/abs/2306.10719
This paper is concerned with the asymptotics of resonances in the semiclassical limit $h\to 0^+$ for $2\times 2$ matrix Schr\"odinger operators in one dimension. We study the case where the two underlying classical Hamiltonian trajectories cross tang
Externí odkaz:
http://arxiv.org/abs/2211.11651
We define resonances for finitely perturbed quantum walks as poles of the scattering matrix in the lower half plane. We show a resonance expansion which describes the time evolution in terms of resonances and corresponding Jordan chains. In particula
Externí odkaz:
http://arxiv.org/abs/2108.01345
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 th
Externí odkaz:
http://arxiv.org/abs/2105.14270
Autor:
Higuchi, Kenta
The aim of this article is to relate the discrete quantum walk on $\mathbb{Z}$ with the continuous Schr\"odinger operator on $\mathbb{R}$ in the scattering problem. Each point of $\mathbb{Z}$ is associated with a barrier of the potential, and the coi
Externí odkaz:
http://arxiv.org/abs/2101.07617