We investigate the stochastic initiation of superradiant emission from a collection of excited two-state atoms coupled through a low-Q cavity mode. Noncollective emission into other modes of the electromagnetic field is included, allowing us to describe the transition from predominantly noncollective to collective behavior as the number of atoms is increased. We examine the dependence of the photon statistics on the number of atoms and the ratio of collective to noncollective decay rates. Numerical results for a few to ${10}^{6}$ atoms are obtained using an approximation scheme developed within the framework of quantum trajectory theory. Results are compared with those for a pure collective emission process and an earlier treatment of noncollective effects.We investigate the stochastic initiation of superradiant emission from a collection of excited two-state atoms coupled through a low-Q cavity mode. Noncollective emission into other modes of the electromagnetic field is included, allowing us to describe the transition from predominantly noncollective to collective behavior as the number of atoms is increased. We examine the dependence of the photon statistics on the number of atoms and the ratio of collective to noncollective decay rates. Numerical results for a few to ${10}^{6}$ atoms are obtained using an approximation scheme developed within the framework of quantum trajectory theory. Results are compared with those for a pure collective emission process and an earlier treatment of noncollective effects.

Physical Review AJan 16, 200221 citations

The initiation of superfluorescence

Roy J. Glauber, Fritz Haake

Physics Letters ASep 1, 1978131 citations

Superfluorescence in CdS/CdSe/CdS Spherical Quantum Wells Modulated by Excitation Geometry

Chunzheng Bai, Qihao Sun, Yiying Zhu +6 more

Superfluorescence (SF) originates from the spontaneous buildup of macroscopic coherence among initially incoherent emitters. Its formation is highly sensitive to dephasing and collective coupling in the system. Here, we observe room-temperature SF in CdS/CdSe/CdS spherical quantum wells. With increasing excitation fluence, the peak emission intensity shows a nearly quadratic increase, while the emission delay and pulse width decrease. Burnham-Chiao ringing is also observed, revealing the characteristic collective radiation dynamics of SF. Further experiments with stripe excitation show that shortening the excitation length L changes the dominant fast emission from amplified spontaneous emission to SF. More importantly, the threshold for SF under stripe excitation is only about 1/30 of that under spot excitation. This large reduction indicates that the propagating radiation field provided by spatially extended excitation favors the buildup of cooperative coherence. These findings provide direct experimental evidence for understanding ultrafast many-body coherence dynamics and offer a route to actively control collective emission at room temperature.Superfluorescence (SF) originates from the spontaneous buildup of macroscopic coherence among initially incoherent emitters. Its formation is highly sensitive to dephasing and collective coupling in the system. Here, we observe room-temperature SF in CdS/CdSe/CdS spherical quantum wells. With increasing excitation fluence, the peak emission intensity shows a nearly quadratic increase, while the emission delay and pulse width decrease. Burnham-Chiao ringing is also observed, revealing the characteristic collective radiation dynamics of SF. Further experiments with stripe excitation show that shortening the excitation length L changes the dominant fast emission from amplified spontaneous emission to SF. More importantly, the threshold for SF under stripe excitation is only about 1/30 of that under spot excitation. This large reduction indicates that the propagating radiation field provided by spatially extended excitation favors the buildup of cooperative coherence. These findings provide direct experimental evidence for understanding ultrafast many-body coherence dynamics and offer a route to actively control collective emission at room temperature.

arXiv:2609.12832Sep 11, 20260 citations

Experiments on the Initiation and Coherence Properties of Superfluorescence

Quirin H. F. Vrehen

Springer series in optical sciences/SPringer series in optical sciencesJan 1, 19791 citation

Coherent Amplification of Continuous Laser Field via Superfluorescence

K. Kitano, H. Maeda

Superfluorescence (SF) is collective spontaneous emission wherein radiators spontaneously synchronize, resulting in an intense single-pulse emission. The avalanche radiation of photons is initiated by the first photon emitted into the SF propagation mode. Because this process is stochastic, the absolute phase of the SF changes randomly from shot to shot. We demonstrate that this phase can be controlled by seeding the SF with a resonant continuous-wave (CW) laser. The seed light was weak enough not to cause the stimulated emission but strong enough to inject the first photon into the SF propagation mode prior to injection by the radiators themselves. Cross-correlation measurements between the seeded SF and CW laser revealed that the seed light was coherently amplified by the SF. The amplification factor for the instantaneous intensity was estimated to be 7 orders of magnitude. These results will pave the way for the development of new types of quantum optical amplifiers.Superfluorescence (SF) is collective spontaneous emission wherein radiators spontaneously synchronize, resulting in an intense single-pulse emission. The avalanche radiation of photons is initiated by the first photon emitted into the SF propagation mode. Because this process is stochastic, the absolute phase of the SF changes randomly from shot to shot. We demonstrate that this phase can be controlled by seeding the SF with a resonant continuous-wave (CW) laser. The seed light was weak enough not to cause the stimulated emission but strong enough to inject the first photon into the SF propagation mode prior to injection by the radiators themselves. Cross-correlation measurements between the seeded SF and CW laser revealed that the seed light was coherently amplified by the SF. The amplification factor for the instantaneous intensity was estimated to be 7 orders of magnitude. These results will pave the way for the development of new types of quantum optical amplifiers.

Physical Review LettersFeb 12, 20243 citations

{10}^{6}

atoms are obtained using an approximation scheme developed within the framework of quantum trajectory theory. Results are compared with those for a pure collective emission process and an earlier treatment of noncollective effects.