23 citations · 155 across the 29 of their papers we have counts for
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Dynamical Instability Induced by Zero Mode Under Symmetry Breaking External Perturbation
J. Takahashi, Y. Nakamura, Y. Yamanaka
A complex eigenvalue in the Bogoliubov-de Gennes equations for a stationary Bose-Einstein condensate in ultracold atomic system indicates the dynamical instability of the system. W…
Formulation for zero mode of Bose-Einstein condensate beyond Bogoliubov approximation
Yusuke Nakamura, Junichi Takahashi, Yoshiya Yamanaka
It is shown for the Bose-Einstein condensate of cold atomic system that the new unperturbed Hamiltonian, which includes not only the first and second powers of the zero mode operat…
Analysis of Particle Transfer by Periodic Lattice Modulation for Ultracold Fermionic Atom Systems in Three Dimensional Optical Lattice
Motoyoshi Inoue, Yusuke Nakamura, Yoshiya yamanaka
We analyze a ultracold fermionic atom system in a three dimensional optical lattice with a confinement harmonic potential, using the Hubbard model, and time-dependent Gutzwiller va…
From Classical Mechanics with Doubled Degrees of Freedom to Quantum Field Theory for Nonconservative System
Y. Kuwahara, Y. Nakamura, Y. Yamanaka
The -matrix structure of Green's functions is a common feature for the real-time formalisms of quantum field theory under thermal situations, such as the closed time pa…