117 citations · 159 across the 8 of their papers we have counts for
8 papers
Band rearrangement through the 3D-Dirac equation with boundary conditions, and the corresponding topological change
Toshihiro Iwai, Boris Zhilinskii
Rearrangement of energy bands against a parameter is studied through the 3D-Dirac equation on a ball in under the APS and the chiral bag boundary conditions on the b…
Topological Phase Transition in a Molecular Hamiltonian with Symmetry and Pseudo-Symmetry, Studied through Quantum, Semi-Quantum and Classical Models
Guillaume Dhont, Toshihiro Iwai, Boris Zhilinskii
The redistribution of energy levels between energy bands is studied for a family of simple effective Hamiltonians depending on one control parameter and possessing axial symmetry a…
Local description of band rearrangements. Comparison of semi-quantum and full quantum approach
Toshihiro Iwai, Boris Zhilinskii
Rearrangement of rotation-vibration energy bands in isolated molecules within semi-quantum approach is characterized by delta-Chern invariants associated to a local semi-quantum Ha…
Qualitative features of the rearrangement of molecular energy spectra from a "wall-crossing" perspective
Boris Zhilinskii, Toshihiro Iwai
Qualitatively different systems of molecular energy bands are studied on example of a parametric family of effective Hamiltonians describing rotational structure of triply degenera…
A new, globally convergent Riemannian conjugate gradient method
Hiroyuki Sato, Toshihiro Iwai
This article deals with the conjugate gradient method on a Riemannian manifold with interest in global convergence analysis. The existing conjugate gradient algorithms on a manifol…
Bipartite entanglement and control in multiqubit systems
Toshihiro Iwai, Yoshiro Yabu
The effect of the control on bipartite entanglement is discussed from a geometric viewpoint for a nuclear magnetic resonance (NMR) system as a model of the n-qubit control system.…
Geometric Approach to Lyapunov Analysis in Hamiltonian Dynamics
Yamaguchi Y. Yoshiyuki, Iwai Toshihiro
As is widely recognized in Lyapunov analysis, linearized Hamilton's equations of motion have two marginal directions for which the Lyapunov exponents vanish. Those directions are t…
Reduction of Quantum Systems on Riemannian Manifolds with Symmetry and Application to Molecular Mechanics
Shogo Tanimura, Toshihiro Iwai
This paper deals with a general method for the reduction of quantum systems with symmetry. For a Riemannian manifold M admitting a compact Lie group G as an isometry group, the quo…