Related papers: Non-additivity in laser-illuminated many-atom syst…
The thermalization of isolated quantum many-body systems is deeply related to fundamental questions of quantum information theory. While integrable or many-body localized systems display non-ergodic behavior due to extensively many…
We demonstrate steady-state, mirrorless superradiance in a cold vapor pumped by weak optical fields. Beyond a critical pump intensity of 1 mW/cm$^2$, the vapor spontaneously transforms into a spatially self-organized state: a density…
We observe a nonlinear optical process in a gas of cold atoms that simultaneously displays the largest reported fifth-order nonlinear susceptibility \chi^(5) = 1.9x10^{-12} (m/V)^4 and high transparency. The nonlinearity results from the…
The optical properties of a fixed atom are well-known and investigated. For example, the extraordinarily large cross section of a single atom as seen by a resonant photon is essential for quantum optical applications. Mechanical effects…
Multimode lasers have a very complex dynamics, as expected when oscillators are nonlinearly coupled. Order emerges when the modes lock together; in this case the coherent superposition of the modes results into a periodic train of pulses or…
When quantum emitters couple indistinguishably to light, they can synchronize into a collective light matter system with radiative properties profoundly different from those of independent particles. To date, the resulting collective…
We theoretically investigate the manipulation of the motional states of trapped ground-state atoms using Rydberg dressing via nonresonant laser fields. The forces resulting from Rydberg-state interaction between dressed neighboring atoms in…
Dissipative light-matter systems can display emergent collective behavior. Here, we report a $\mathbb{Z}_2$-symmetry-breaking phase transition in a system of multi-level $^{87}$Rb atoms strongly coupled to a weakly driven two-mode optical…
Trapped Rydberg ions represent a flexible platform for quantum simulation and information processing which combines a high degree of control over electronic and vibrational degrees of freedom. The possibility to individually excite ions to…
The motion-induced drag force acting on a particle moving parallel to an arrangement of $N$ objects is analyzed. Particular focus is placed on the nonequilibrium statistics of the interaction and on the interplay between the system's…
Nonlinear spectroscopy employs a series of laser pulses to interrogate dynamics in large interacting many-body systems, and has become a highly successful method for experiments in chemical physics. Current quantum optical experiments…
The laser-excitation of Rydberg atoms in ultracold gases is often described assuming that the atomic motion is frozen during the excitation time. We show that this frozen gas approximation can break down for atoms that are held in optical…
Quantum fluctuations of optical fiber Bragg grating solitons are investigated numerically by the back-propagation method. It is found for the first time that the bandgap effects of the grating act as a nonlinear filter and cause the soliton…
Interactions between many-body atomic systems in optical lattices and light in cavities induce long-range and correlated atomic dynamics beyond the standard Bose-Hubbard model, due to the global nature of the light modes. We characterise…
We present a theoretical study of strong laser-atom interactions, when the laser field parameters are subjected to random processes. The atom is modelled by a two-level and three-level systems, while the statistical fluctuations of the…
Quadrature squeezing of light is investigated in a hybrid atom-optomechanical system comprising a cloud of two-level atoms and a movable mirror mediated by a single-mode cavity field. When the system is at high temperatures with quadrature…
There is currently a strong interest in mirrorless lasing systems, in which the electromagnetic feedback is provided either by disorder (multiple scattering in the gain medium) or by order (multiple Bragg reflection). These mechanisms…
Optical trapping and binding systems are non-Hermitian. On one hand, the optical force is non-Hermitian and may pump energy into the trapped particle when the non-Hermiticity is sufficiently large. On the other hand, the ambient damping…
We study, both theoretically and experimentally, the Bragg scattering of light in optically-induced photonic lattices and reveal the key physical mechanisms which govern nonlinear self-action of narrow beams under the combined effects of…
Multiparticle entangled states generated via interaction between narrow-band light and an ensemble of identical two-level atoms are considered. Depending on the initial photon statistics, correlation between atoms and photons can give rise…