232 citations · 1.3k across the 64 of their papers we have counts for
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A Fundamental Limit of Measurement Imposed by the Elementary Interactions
Akira Shimizu
Quantum information theory is closely related to quantum measurement theory because one must perform measurement to obtain information on a quantum system. Among many possible limi…
Nonequilibrium Mesoscopic Conductors Driven by Reservoirs
Akira Shimizu, Hiroaki Kato
In order to specify a nonequilibrium steady state of a quantum wire (QWR), one must connect reservoirs to it. Since reservoirs should be large 2d or 3d systems, the total system is…
Dicke Superradiance in a magnetoplasma
Tobias Brandes, Jun'ichi Inoue, Akira Shimizu
We present theoretical results for superradiance, i.e. the collective coherent decay of a radiating system, in a semiconductor heterostructure under a strong quantizing magnetic fi…
Dicke-superradiance in electronic systems coupled to reservoirs
T. Brandes, J. Inoue, A. Shimizu
We present theoretical results for superradiance, i.e. the collective coherent decay of a radiating system, in semiconductor structures. An optically active region can become super…
Pump Built-in Hamiltonian Method for Pump-Probe Spectroscopy
Jun-ichi Inoue, Akira Shimizu
We propose a new method of calculating nonlinear optical responses of interacting electronic systems. In this method, the total Hamiltonian (system + system-pump interaction) is tr…
Renormalized Bosonic Interaction of Excitons
Jun-ichi Inoue, Tobias Brandes, Akira Shimizu
An effective bosonic Hamiltonian of excitons with ``spin'' degrees of freedom in two dimension is obtained through a projection procedure, starting from a conventional electro…
Statistical Theory of Energy Transfer to Small and Chaotic Quantum Systems Induced by a Slowly-Varying External Field
Yasuhiro Higashiyama, Akira Shimizu
We study nonequilibrium properties of small and chaotic quantum systems, i.e., non-integrable systems whose size is small in the sense that the separations of energy levels are non…
Strong Enhancement of Superconducting Correlation in a Two-Component Fermion Gas
Masaki Shigemori, Akira Shimizu, Tobias Brandes +1
We study high-density electron-hole (e-h) systems with the electron density slightly larger than the hole density. We find a new superconducting phase, in which the excess electron…