Related papers: Time Evolution of Superradiance
We theoretically investigate the scattering process of Bogoliubov excitations on a rotating photon-fluid. Using the language of Noether currents we demonstrate the occurrence of a resonant amplification phenomenon, which reduces to the…
The ultrafast dynamic evolution of an atomic system under medium-strength laser fields is studied by performing transient absorption measurement. An analytical model developed from perturbation theory with a modified transition dipole…
Ultra-cold atomic systems are among the most promising platforms that have the potential to shed light on the complex behavior of many-body quantum systems. One prominent example is the case of a dense ensemble illuminated by a strong…
An individual excited two level system decays to its ground state by emitting a single photon in a process known as spontaneous emission. In accordance with quantum theory the probability of detecting the emitted photon decreases…
Using the time-dependent theory of quantum mechanics, we investigate nuclear electric dipole responses. The time evolution of a wave function is explicitly calculated in the coordinate-space representation. The particle continuum is treated…
Spectral properties of super-Eddington accretion flows are investigated by means of a parallel line-of-sight calculation. The subjacent model, taken from two-dimensional radiation hydrodynamic simulations by Ohsuga et al. (2005), consists…
The Hamiltonian of the two-photon Dicke model is diagonalized for the normal phase and super-radiant phase beyond the mean-field method respectively, giving the critical coupling strength. Besides a spectral collapse, the super-radiant…
Photon propagation in a gas of N atoms is studied using an effective Hamiltonian describing photon mediated atomic dipolar interactions. The density P(\Gamma) of photon escape rates is determined from the spectrum of the N x N random matrix…
Radiative transfer calculations of massive star formation are presented. These are based on the Turbulent Core Model of McKee & Tan and self-consistently included a hydrostatic core, an inside-out expansion wave, a zone of free-falling…
When a photon is sent onto an atomic ensemble, it interacts collectively with the $N$ atoms of the sample and not simply with one of them. This results in measurable modifications in the scattering rate, the emission diagram or the temporal…
We have applied the concept of superradiance introduced by Dicke in 1954 to astrophysics by extending the corresponding analysis to the magnetic dipole interaction characterizing the atomic hydrogen 21 cm line. Although it is unlikely that…
We introduce kinetically constrained superradiance, a form of cooperative emission in which interactions imprint configuration-dependent energy shifts on optical transitions, splitting Dicke superradiance into multiple, frequency-resolved…
We study theoretically the driven-dissipative dynamics of an array of two-level emitters, coupled to a single photonic mode, in the presence of disorder in the resonant frequencies. We introduce the notion of subradiant correlations in the…
We investigate the dynamical properties of the finite-size Dicke model coupled to a photon reservoir in the dispersive regime. The system-reservoir coupling in our Hamiltonian includes counter-rotating terms, which are relevant in the…
We develop a unification scheme which explains the varied observed properties of TDEs in terms of simple disc physics. The unification scheme postulates that the different observed properties of TDEs are controlled by the peak Eddington…
We establish a new theoretical framework, based on a time-dependent mean field approach, to address the dynamics of the driven Dicke model. The joint evolution of both mean fields and quantum fluctuations gives rise to a rich and generally…
The analysis of single-mode photon fluctuations and their counting statistics at the superradiant phase transition is presented. The study concerns the equilibrium Dicke model in a regime where the Rabi frequency, related to a coupling of…
The Dicke superradiance on vibronic transitions of impurity crystals is considered. It is shown that parameters of the superradiance (duration and intensity of the superradiance pulse and delay times) on each vibronic transition depend on…
We consider the problem of two-photon cooperative emission in systems of two-level atoms. Two physically distinct regimes are analyzed. First, we investigate the case of a small number of atoms. We study the evolution of two-photon super-…
We present simulations of the superradiant dynamics of ensembles of atoms in the presence of collective and individual atomic decay processes. We unravel the density matrix with Monte-Carlo wave-functions and identify the quantum jumps in a…