232 citations · 1.3k across the 64 of their papers we have counts for
10 papers · 1 filter
Time evolution of condensed state of interacting bosons with reduced number fluctuation in a leaky box
Akira Shimizu, Jun-ichi Inoue
We study the time evolution of the Bose-Einstein condensate of interacting bosons confined in a leaky box, when its number fluctuation is initially (t=0) suppressed. We take accoun…
Effective Hamiltonian for Excitons with Spin Degrees of Freedom
Jun-ichi Inoue, Tobias Brandes, Akira Shimizu
Starting from the conventional electron-hole Hamiltonian , we derive an effective Hamiltonian for excitons with spin degrees of freedom. T…
Quantum Langevin equations for semiconductor light-emitting devices and the photon statistics at a low-injection level
Hiroshi Fujisaki, Akira Shimizu
From the microscopic quantum Langevin equations (QLEs) we derive the effective semiconductor QLEs and the associated noise correlations which are valid at a low-injection level and…
Fundamentals of Electron-Photon Interaction in Nanostructures
Akira Shimizu
We describe the fundamental equations for description of electron-photon interactions in insulating nanostructures. Since the theory for the nanostructures are based on the theory…
Quantum Optics in Dispersive and Absorptive Media
Akira Shimizu, Teruaki Okushima, Kazuki Koshino
Using microscopic models in which both photons and excitons are treated as microscopic degrees of freedom, we discuss polaritons of two cases: One is the case when excitonic parame…
Quantum Measurement and Fluctuations in Nanostructures
Akira Shimizu
Measurement and fluctuations are closely related to each other in quantum mechanics. This fact is explicitly demonstrated in the case of a quantum non-demolition photodetector whic…
Landauer Conductance and Nonequilibrium Noise of One-Dimensional Interacting Electron Systems
Akira Shimizu
The conductance of one-dimensional interacting electron systems is calculated in a manner similar to Landauer's argument for non-interacting systems. Unlike in previous studies in…
Interacting One-Dimensional Electrons Driven by Two-Dimensional Reservoir Electrons
Akira Shimizu, Takayuki Miyadera
We derive an effective 1D theory from the Hamiltonian of the 3D system which consists of a mesoscopic conductor and reservoirs. We assume that the many-body interaction have the sa…
First-kind measurements, non-demolition measurements, and conservation laws
Akira Shimizu, Kazuko Fujita
A general discussion is given for first-kind (FK) and quantum non-demolition (QND) measurements. The general conditions for these measurements are derived, including the most gener…
Oscillatory behavior of a superradiating system coupled to electron reservoirs
T. Brandes, J. Inoue, A. Shimizu
We investigate a superradiating system coupled to external reservoirs. Under conditions where electrons tunneling at a rate act like an electron pump, we predict a novel phenom…