We theoretically analyze a novel evaporative cooling scheme applicable to Rydberg chains. We consider an initially thermal chain of circular Rydberg atoms confined to a one-dimensional (1D) setting in the absence of periodic potentials. We show that the evaporation of about one half of the atoms of the chain brings it near its quantum ground state, which is a 1D Rydberg crystal. We describe the scheme thermodynamically, applying the truncated Boltzmann distribution to the collective excitations of the chain, and show that it leads to a novel quasi--equilibrium many-body state. The evaporation is driven by slowly compressing the chain. For a given atom number, this process is adiabatic down to a minimal chain size. At this point, a single atom is expelled, causing the energy and entropy per particle to decrease. Then, adiabatic compression resumes. For longer chains, comprising about $1000$ atoms, we emphasize the quasi-universality of the evaporation curve.We theoretically analyze a novel evaporative cooling scheme applicable to Rydberg chains. We consider an initially thermal chain of circular Rydberg atoms confined to a one-dimensional (1D) setting in the absence of periodic potentials. We show that the evaporation of about one half of the atoms of the chain brings it near its quantum ground state, which is a 1D Rydberg crystal. We describe the scheme thermodynamically, applying the truncated Boltzmann distribution to the collective excitations of the chain, and show that it leads to a novel quasi--equilibrium many-body state. The evaporation is driven by slowly compressing the chain. For a given atom number, this process is adiabatic down to a minimal chain size. At this point, a single atom is expelled, causing the energy and entropy per particle to decrease. Then, adiabatic compression resumes. For longer chains, comprising about $1000$ atoms, we emphasize the quasi-universality of the evaporation curve.

Nov 14, 20190 citations

Angular-momentum-state distribution of sodium atoms photoassociated in a magneto-optical trap

James P. Shaffer, Witek Chalupczak, N. P. Bigelow

We present direct spectroscopic measurement of the excited state angular-momentum-state distribution of ${\mathrm{Na}}_{2}^{*}(3{}^{2}{S}_{1/2}+3{}^{2}{P}_{3/2})$ molecules photoassociated by the trapping lasers in a sodium magneto-optical trap. We find that states with quantum numbers up to $J=22$ are excited and that the measured population distribution can be well described using a local equilibrium model.We present direct spectroscopic measurement of the excited state angular-momentum-state distribution of ${\mathrm{Na}}_{2}^{*}(3{}^{2}{S}_{1/2}+3{}^{2}{P}_{3/2})$ molecules photoassociated by the trapping lasers in a sodium magneto-optical trap. We find that states with quantum numbers up to $J=22$ are excited and that the measured population distribution can be well described using a local equilibrium model.

Physical Review AJan 5, 20015 citations

Spatial Distribution of Excited States

Optical science and engineeringNov 29, 20040 citations

The Nature of the Electronic Excited States of Molecular Systems

Baldassare Di Bartolo

NATO ASI series. Series B : PhysicsJan 1, 19920 citations

Matrix product state of multi-time correlations

Katja Klobas, Matthieu Vanicat, Juan P. Garrahan +1 more

Abstract For an interacting spatio-temporal lattice system we introduce a formal way of expressing multi-time correlation functions of local observables located at the same spatial point with a time state , i.e. a statistical distribution of configurations observed along a time lattice. Such a time state is defined with respect to a particular equilibrium state that is invariant under space and time translations. The concept is developed within the rule 54 reversible cellular automaton, for which we explicitly construct a matrix product form of the time state, with matrices that act on the three-dimensional auxiliary space. We use the matrix-product state to express equal-space time-dependent density-density correlation function, which, for special maximum-entropy values of equilibrium parameters, agrees with the previous results. Additionally, we obtain an explicit expression for the probabilities of observing all multi-time configurations, which enables us to study distributions of times between consecutive excitations and prove the absence of decoupling of timescales in the rule 54 model.Abstract For an interacting spatio-temporal lattice system we introduce a formal way of expressing multi-time correlation functions of local observables located at the same spatial point with a time state , i.e. a statistical distribution of configurations observed along a time lattice. Such a time state is defined with respect to a particular equilibrium state that is invariant under space and time translations. The concept is developed within the rule 54 reversible cellular automaton, for which we explicitly construct a matrix product form of the time state, with matrices that act on the three-dimensional auxiliary space. We use the matrix-product state to express equal-space time-dependent density-density correlation function, which, for special maximum-entropy values of equilibrium parameters, agrees with the previous results. Additionally, we obtain an explicit expression for the probabilities of observing all multi-time configurations, which enables us to study distributions of times between consecutive excitations and prove the absence of decoupling of timescales in the rule 54 model.

arXiv:1912.09742Journal of Physics A Mathematical and TheoreticalApr 23, 202035 citations

1000

atoms, we emphasize the quasi-universality of the evaporation curve.

We present direct spectroscopic measurement of the excited state angular-momentum-state distribution of

{\mathrm{Na}}_{2}^{*}(3{}^{2}{S}_{1/2}+3{}^{2}{P}_{3/2})

molecules photoassociated by the trapping lasers in a sodium magneto-optical trap. We find that states with quantum numbers up to

J=22

are excited and that the measured population distribution can be well described using a local equilibrium model.