Stefan Schütz

University of Strasbourg

Phase (waves)PhysicsDissipationOrders of magnitude (time)Phase transitionThermalisationPhotonAtomic physicsField (physics)Optical cavityScatteringCondensed matter physicsRelaxation (physics)Steady stateStationary stateLaserSemiclassical physicsMomentumRadiative transferMetastabilityDissipative system

13Publications

8H-index

155Citations

Publications 10

#1Tim Keller (Saarland University)H-Index: 3

#2Valentin TorgglerH-Index: 5

Last. Giovanna Morigi (Saarland University)H-Index: 34

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A cold dilute atomic gas in an optical resonator can be radiatively cooled by coherent scattering processes when the driving laser frequency is tuned close to but below the cavity resonance. When the atoms are sufficiently illuminated, their steady state undergoes a phase transition from a homogeneous distribution to a spatially organized Bragg grating. We characterize the dynamics of this self-ordering process in the semi-classical regime when distinct cavity modes with commensurate wavelengths...

#1Simon B. JägerH-Index: 8

#2Minghui XuH-Index: 8

Last. Giovanna MorigiH-Index: 34

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We analyse the dynamics leading to radiative cooling of an atomic ensemble confined inside an optical cavity when the atomic dipolar transitions are incoherently pumped and can synchronize. Our study is performed in the semiclassical regime and assumes that cavity decay is the largest rate in the system dynamics. We identify three regimes characterising the cooling. At first hot atoms are individually cooled by the cavity friction forces. After this stage, the atoms' center-of-mass motion is fur...

#1Stefan Schütz (Saarland University)H-Index: 8

#2Simon B. Jäger (Saarland University)H-Index: 8

Last. Giovanna Morigi (Saarland University)H-Index: 34

view all 3 authors...

We theoretically characterize the semiclassical dynamics of an ensemble of atoms after a sudden quench across a driven-dissipative second-order phase transition. The atoms are driven by a laser and interact via conservative and dissipative long-range forces mediated by the photons of a single-mode cavity. These forces can cool the motion and, above a threshold value of the laser intensity, induce spatial ordering. We show that the relaxation dynamics following the quench exhibits a long pretherm...

#1Simon B. Jäger (Saarland University)H-Index: 8

#2Stefan Schütz (Saarland University)H-Index: 8

Last. Giovanna Morigi (Saarland University)H-Index: 34

view all 3 authors...

Photons mediate long-range optomechanical forces between atoms in high-finesse resonators, which can induce the formation of ordered spatial patterns. When a transverse laser drives the atoms, the system undergoes a second-order phase transition that separates a uniform spatial density from a Bragg grating maximizing scattering into the cavity and is controlled by the laser intensity. Starting from a Fokker-Planck equation describing the semiclassical dynamics of the Natom distribution functi...

#1Stefan SchützH-Index: 8

#2Simon B. JägerH-Index: 8

Last. Giovanna MorigiH-Index: 34

view all 3 authors...

We theoretically characterize the semiclassical dynamics of an ensemble of atoms after a sudden quench across a driven-dissipative second-order phase transition. The atoms are driven by a laser and interact via conservative and dissipative long-range forces mediated by the photons of a single-mode cavity. These forces can cool the motion and, above a threshold value of the laser intensity, induce spatial ordering. We show that the relaxation dynamics following the quench exhibits a long pretherm...

#1Stefan Schütz (Saarland University)H-Index: 8

#2Simon B. Jäger (Saarland University)H-Index: 8

Last. Giovanna Morigi (Saarland University)H-Index: 34

view all 3 authors...

Pattern formation of atoms in high-finesse optical resonators results from the mechanical forces of light associated with superradiant scattering into the cavity mode. It occurs when the laser intensity exceeds a threshold value such that the pumping processes counteract the losses. We consider atoms driven by a laser and coupling with a mode of a standing-wave cavity and describe their dynamics with a Fokker-Planck equation, in which the atomic motion is semiclassical but the cavity field is a ...

#1Stefan Schütz (Saarland University)H-Index: 8

#2Giovanna Morigi (Saarland University)H-Index: 34

Atoms can spontaneously form spatially-ordered structures in optical resonators when they are transversally driven by lasers. This occurs when the laser intensity exceeds a threshold value and results from the mechanical forces on the atoms associated with superradiant scattering into the cavity mode. We treat the atomic motion semiclassically and show that, while the onset of spatial ordering depends on the intracavity-photon number, the stationary momentum distribution is a Maxwell-Boltzmann w...

#1Stefan SchützH-Index: 8

#2Giovanna MorigiH-Index: 34

Atoms can spontaneously form spatially-ordered structures in optical resonators when they are transversally driven by lasers. This occurs when the laser intensity exceeds a threshold value and results from the mechanical forces on the atoms associated with superradiant scattering into the cavity mode. We treat the atomic motion semiclassically and show that, while the onset of spatial ordering depends on the intracavity-photon number, the stationary momentum distribution is a Maxwell-Boltzmann w...

#1Stefan SchützH-Index: 8

#2Hessam HabibianH-Index: 7

Last. Giovanna MorigiH-Index: 34

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The semiclassical dynamics of atoms are theoretically studied, when the atoms are confined inside a standing-wave high-finesse resonator. The atoms are cooled by scattering processes in which the photons of a transverse laser are coherently scattered into the cavity mode. We derive a Fokker-Planck equation for the atomic center-of-mass variables which allows us to determine the equations of motion in the semiclassical limit for any value of the intensity of the laser field. We extract its predic...

#1Wolfgang NiedenzuH-Index: 15

#2Stefan SchützH-Index: 8

Last. Helmut Ritsch (University of Innsbruck)H-Index: 55

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When atoms scatter photons from a transverse laser into a high-finesse optical cavity, they form crystalline structures which maximize the intracavity light field and trap the atoms in the ordered array. Stable organization occurs when the laser field amplitude exceeds a certain threshold. For planar single-mode cavities there exist two equivalent possible atomic patterns, which determine the phase of the intracavity light field. Under these premises, we show that the effect of an additional las...