Full Counting Statistics of Laser Excited Rydberg Aggregates in a One-Dimensional Geometry

Abstract

We experimentally study the full counting statistics of few-body Rydberg aggregates excited from a quasi-one-dimensional atomic gas. We measure asymmetric excitation spectra and increased second and third order statistical moments of the Rydberg number distribution, from which we determine the average aggregate size. Estimating rates for different excitation processes we conclude that the aggregates grow sequentially around an initial grain. Direct comparison with numerical simulations confirms this conclusion and reveals the presence of liquidlike spatial correlations. Our findings demonstrate the importance of dephasing in strongly correlated Rydberg gases and introduce a way to study spatial correlations in interacting many-body quantum systems without imaging.

Dynamic formation of Rydberg aggregates at off-resonant excitation

“…Finally, we note that very recently, super-Poissonian excitation statistics have been observed in experiments operating at off-resonant driving in the strongly dissipative regime [40,41]. We expect that the mechanism of aggregate formation discussed here leading to a bimodal distribution of excitation numbers still applies in the presence of substantial decoherence.…”

“…We expect that the mechanism of aggregate formation discussed here leading to a bimodal distribution of excitation numbers still applies in the presence of substantial decoherence. The main difference would be that, rather than resonantly excited pairs, off-resonantly excited single atoms function as initial grains for the aggregate formation [40].…”

Control of Rydberg-atom blockade by dc electric-field orientation in a quasi-one-dimensional sample

“…For example, overcoming the density limitation of Rydberg atoms may be important for time dependent experiments where the direction of the field can be changed suddenly, taking the system from a low interacting condition to a high interacting regime. That may be useful for the study of many-body effects in a strongly-coupled systems in condensed matter physics [19][20][21]23]. The suppression of the dipoledipole interaction at the magic angle is also very significant because allows one to perform experiments where high order interactions may be investigated in more details, for instance dipole-quadrupole, extracting information of intrinsic properties of interatomic potentials that were previously unachievable.…”

“…Such works explore different aspects of condensed matter physics: i) transition to the crystalline phase [19,20]; ii) energy transport [21]; iii) spatial correlations [22]; iv) Rydberg aggregates [23]; v) van der Waals interaction and Rydberg blockade effect [24][25][26]. Clearly, Rydberg atoms can be used as a prototype for the study of such complex properties because they are a simpler system and easier to control.…”

Experimental observation of controllable kinetic constraints in a cold atomic gas

“…The interparticle distance below which this blockade constraint becomes important is given by the (incoherent) blockade radius r b = (C 6 / γ ) 1 6 . By contrast, for > 0 the off-resonant single-atom excitation rate is small, but now a facilitation constraint appears [10]: An excited atom somewhere in the system shifts atoms contained within a shell of radius r fac and width δr fac into resonance, where r fac = (C 6 / ) 1 6 , which corresponds to the van der Waals interaction compensating the laser detuning [12,[17][18][19][20][21][22], and δr fac = r fac 6 γ . We will show that this leads to strikingly different features in the excitation dynamics in comparison to the case of resonant excitation.…”