Related papers: Recombination fluorescence in ultracold neutral pl…
Population dynamics in weakly-excited clouds of ultracold $^{87}$Rb Rydberg atoms were studied by means of trap loss, fluorescence detection, and state dependent stimulated emission. Rydberg atoms were excited to various nl Rydberg states…
We present the experimental observation of the antiblockade in an ultracold Rydberg gas recently proposed by Ates et al. [Phys. Rev. Lett. 98, 023002 (2007)]. Our approach allows the control of the pair distribution in the gas and is based…
We study the photon statistics of weak coherent pulses propagating through a cold Rydberg atomic ensemble in the regime of Rydberg electromagnetically induced transparency. We show experimentally that the value of the second-order…
Photo-absorption in fully ionized plasmas in high magnetic fields is re-examined, using the methods of many-body quantum field theory. For frequencies in the immediate vicinity of the electron cyclotron resonance the rates we obtain…
A general expression for the double differential cross section of fluorescence radiation following photorecombination (PRF) of polarized electrons and polarized ions is derived by using usual atomic theory methods and is represented in the…
Ultracold Rb atoms were used to demonstrate non-degenerate four-wave mixing through a Rydberg state. Continuous 5S-5P-nD two-photon excitation to the Rydberg state was combined with an nD-6P tuned laser in a phase matched geometry. The…
Light-matter interactions are of fundamental scientific and technological interest. Ultrafast electron microscopy and diffraction with combined femtosecond-nanometer resolution elucidate the laser-induced dynamics in structurally…
Reabsorption, the multiple scattering of spontaneously emitted photons in optically thick gases, is a major limitation to efficient optical pumping and laser cooling in ultracold gases. We report mitigation of reabsorption using spatial and…
The bremsstrahlung cross section for relativistic electrons in a crystal is split into the sum of coherent and incoherent parts (the last is due to a thermal motion of atoms in the crystal). Although the spectrum of incoherent radiation in…
The understanding of dynamical evolutions of interacting photon pulses in Rydberg atomic ensemble is the prerequisite for realizing quantum devices with such system. We present an approach that efficiently simulates the dynamical processes,…
Cold atom interferometers use guiding potentials that split the wave function of the Bose-Einstein condensate and then recombine it. We present theoretical analysis of the wave function recombination instability that is due to the weak…
The expansion of ultracold neutral plasmas (UCP) is driven primarily by the thermal pressure of the electron component and is therefore sensitive to the electron temperature. At lower densities (less than 10$^8$ /cm$^3$), evaporative…
Ultrafast spectroscopy is an emerging technique with great promise in the study of quantum materials, as it makes it possible to track similarities and correlations that are not evident near equilibrium. Thus far, however, the way in which…
We report the sudden and spontaneous evolution of an initially correlated gas of repulsively interacting Rydberg atoms to an ultracold plasma. Under continuous laser coupling we create a Rydberg ensemble in the strong blockade regime, which…
The physical ingredients to describe the epoch of cosmological recombination are amazingly simple and well-understood. This fact allows us to take into account a very large variety of processes, still finding potentially measurable…
As atoms formed for the first time during primordial recombination, they emitted bound-bound and free-bound radiation leading to spectral distortions to the cosmic microwave background. These distortions might become observable in the…
Femtosecond coherent multidimensional spectroscopy is demonstrated for an ultracold gas. For this, a setup for phase modulation spectroscopy is used to probe the $3^2\mathrm{S}_{1/2} - 2^2\mathrm{P}_{1/2, 3/2}$ transition in an 800…
Context. Flare Hard X-Rays (HXRs) from non-thermal electrons are commonly treated as solely bremsstrahlung (f-f), recombination (f-b) being neglected. This assumption is shown to be substantially in error, especially in hot sources, mainly…
We report optical absorption imaging of ultracold neutral plasmas.Images are used to measure the ion absorption spectrum, which is Doppler-broadened. Through the spectral width, we monitor ion equilibration in the first 250ns after plasma…
We show that the precise preparation of a quantum superposition between three rotational states of an ultracold dipolar molecule generates controllable interferences in their two-body scattering dynamics and collisional rate coefficients,…