Related papers: Nonclassical photon pairs from warm atomic vapor u…
The generation of entangled photon pairs which are compatible with quantum devices and standard telecommunication channels are critical for the development of long range fiber quantum networks. Aside from wavelength, bandwidth matching and…
We characterize a source of photon pairs based on cascade decay in a cold Rb-87 ensemble. This source is particularly suited to generate of photons for interaction with Rb-87 based atomic systems. We experimentally investigate the…
We report on the triggered generation of indistinguishable photons by solid-state single-photon sources in two separate cryogenic laser scanning microscopes. Organic fluorescent molecules were used as emitters and investigated by means of…
We analyze the emergence of correlated optical phenomena in the transmission of light through a waveguide that confines classical or ultracold quantum degenerate atomic ensembles. The conditions of the correlated collective response are…
We describe a method for non-degenerate four-wave mixing in a cold sample of 4-level atoms. An integral part of the four-wave mixing process is a collective instability which spontaneously generates a periodic density modulation in the cold…
The realization of correlated multi-photon processes usually depends on the interaction between nonlinear media and atoms. However, the nonlinearity of optical materials is generally weak, making it still very challenging to achieve…
Somewhat surprisingly, quantum features can be extracted from a classical bath. For this, we discuss a sample of three-level atoms in ladder configuration interacting only via the surrounding bath, and show that the fluorescence light…
The controlled interaction between a single, trapped, laser-driven atom and the mode of a high-finesse optical cavity allows for the generation of temporally separated, entangled light pulses. Entanglement between the photon-number…
Superradiant biphoton emission from atomic ensembles provides a powerful route to generating highly correlated quantum light, yet its microscopic physical origin has remained incompletely understood. In particular, it is often unclear how…
We propose and analyze a new method to produce single and entangled photons which does not require cavities. It relies on the collective enhancement of light emission as a consequence of the presence of entanglement in atomic ensembles.…
We have built a compact light source for bright squeezed twin-beams at 795\,nm based on four-wave-mixing in atomic $^{85}$Rb vapor. With a total optical power of 400\,mW derived from a free running diode laser and a tapered amplifier to…
Entangled photons are a crucial resource for quantum communication and linear optical quantum computation. Unfortunately, the applicability of many photon-based schemes is limited due to the stochastic character of the photon sources.…
Observing nonlinear optical quantum effects or implementing quantum information protocols using nonlinear optics requires moving to ever-smaller input light intensities. However, low light intensities generally mean weak optical…
We study both experimentally and theoretically the generation of photon pairs by spontaneous four-wave mixing (SFWM) in standard birefringent optical fibers. The ability to produce a range of two-photon spectral states, from highly…
Nonclassical state is an essential resource for quantum-enhanced communication, computing and metrology to outperform their classical counterpart. The nonclassical states that can operate at high bandwidth and room temperature while being…
Nonlinear Compton scattering driven by ultraintense lasers presents a promising avenue for enhancing the photon energy, brilliance, and setup compactness of $\gamma$-ray sources. However, a significant challenge lies in achieving a high…
We investigate the collective scattering of coherent light from a thermal alkali-metal vapor with temperatures ranging from 350 to 450 K, corresponding to average atomic spacings between $0.7 \lambda$ and $0.1 \lambda$. We develop a…
We study the generation of intensity quantum correlations using four-wave mixing in a rubidium vapor. The absence of cavity in these experiments allows to deal with several spatial modes simultaneously. In the standard, amplifying,…
We address joint photodetection as a method to discriminate between the classical correlations of a thermal beam divided by a beam splitter and the quantum entanglement of a twin-beam obtained by parametric downconversion. We show that for…
Spin-polarised atomic ensembles probed by light based on the Faraday interaction are a versatile platform for numerous applications in quantum metrology and quantum information processing. Here we consider an ensemble of Alkali atoms that…