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Related papers: Threshold of a Random Laser with Cold Atoms

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In a random laser (RL), a system possessing in itself both resonator and amplifying medium while lacking of a macroscopic cavity, the feedback is provided by the scattering, which forces light to travel across very long random paths. Here…

Optics · Physics 2015-06-15 Marco Leonetti , Cefe Lopez

We realize a laser with a cloud of cold rubidium atoms as gain medium, placed in a low-finesse cavity. Three different regimes of laser emission are observed corresponding respectively to Mollow, Raman and Four Wave Mixing mechanisms. We…

Atomic Physics · Physics 2008-08-30 William Guerin , Franck Michaud , Robin Kaiser

We study the interaction of a nearly resonant linearly polarized laser beam with a cloud of cold cesium atoms in a high finesse optical cavity. We show theoretically and experimentally that the cross-Kerr effect due to the saturation of the…

The mode dynamics of a random laser is investigated in experiment and theory. The laser consists of a ZnCdO/ZnO multiple quantum well with air-holes that provide the necessary feedback. Time-resolved measurements reveal multimode spectra…

Optics · Physics 2015-10-09 M. Höfner , H. -J. Wünsche , F. Henneberger

A novel laser cooling mechanism based on many body effects is presented. The method can be applicable for cooling a large class of atoms and molecules in higher density than commonly excepted by existing methods. The cooling mechanism…

Atomic Physics · Physics 2021-03-11 Roie Dann , Ronnie Kosloff

We present optical Thomson scattering measurements of electron density and temperature in a large-scale (~2 cm) exploding laser plasma produced by irradiating a solid target with a high energy (5-10 J) laser pulse at high repetition rate (1…

While conventional lasers are based on gain media with three or four real levels, unconventional lasers including virtual levels and two-photon processes offer new opportunities. We study lasing that involves a two-photon process through a…

Quantum Physics · Physics 2019-01-23 Hannes Gothe , Dmitriy Sholokhov , Anna Breunig , Martin Steinel , Jürgen Eschner

Individual laser cooled atoms are delivered on demand from a single atom magneto-optic trap to a high-finesse optical cavity using an atom conveyor. Strong coupling of the atom with the cavity field allows simultaneous cooling and detection…

Quantum Physics · Physics 2009-11-13 Kevin M. Fortier , Soo Y. Kim , Michael J. Gibbons , Peyman Ahmadi , Michael S. Chapman

An optical microtrap is realized on a dielectric surface by crossing a tightly focused laser beam with an horizontal evanescent-wave atom mirror. The nondissipative trap is loaded with $\sim$$10^5$ cesium atoms through elastic collisions…

Atomic Physics · Physics 2009-11-07 M. Hammes , D. Rychtarik , H. -C. Nägerl , R. Grimm

We investigate hitherto unexplored regimes of probe scattering by atoms trapped in optical lattices: weak scattering by effectively random atomic density distributions and multiple scattering by arbitrary atomic distributions. Both regimes…

Atomic Physics · Physics 2009-11-06 M. Blaauboer , G. Kurizki , V. M. Akulin

The work was aimed to generate random laser emissions simultaneously at two wavelengths in a weakly scattering system containing mixture of binary dyes, rhodamine-B (Rh-B) and oxazine-170 (O-170) dispersed with ZnO nano-particles served as…

Optics · Physics 2016-08-29 Sunita Kedia , Sucharita Sinha

Theoretical studies of superradiant lasing on optical clock transitions predict a superb frequency accuracy and precision closely tied to the bare atomic linewidth. Such a superradiant laser is also robust against cavity fluctuations when…

Quantum Physics · Physics 2021-11-02 Anna Bychek , Christoph Hotter , David Plankensteiner , Helmut Ritsch

Random lasing occurs as the result of a coherent optical feedback from multiple scattering centers. Here, we demonstrate that plasmonic gold nanostars are efficient light scattering centers, exhibiting strong field enhancement at their…

We measure the coherent scattering of low-intensity, near-resonant light by a cloud of laser-cooled two-level rubidium atoms with a size comparable to the wavelength of light. We isolate a two-level atomic structure by applying a 300G…

A numerical study is presented of one-dimensional and two-dimensional random lasers as a function of the pumping rate above the threshold for lasing. Depending on the leakiness of the cavity modes, we observe that the stationary lasing…

Optics · Physics 2011-08-17 Jonathan Andreasen , Patrick Sebbah , Christian Vanneste

We employ semiclassical theoretical analysis to study laser cooling of free atoms using three-level cascade transitions, where the upper transition is much weaker than the lower one. This represents an alternate cooling scheme, particularly…

Atomic Physics · Physics 2015-06-16 Flavio C. Cruz , Michael L. Sundheimer , Wictor C. Magno

We demonstrate that there is a fundamental limit to the sensitivity of phase-based detection of atoms with light for a given maximum level of allowable spontaneous emission. This is a generalisation of previous results for two-level and…

Quantum Physics · Physics 2009-11-10 J. J. Hope , J. D. Close

We have demonstrated an atom-optical lens, with the advantage of a small scale and flexible adjustment of the parameters, realized by a far red-detuned Gaussian laser beam perpendicular to the propagation direction of the cold atomic cloud.…

Quantum Physics · Physics 2015-01-29 Zhenglu Duan , Shuyu Zhou , Tao Hong , Yuzhu Wang

The threshold properties of photonic crystal quantum dot lasers operating in the slow-light regime are investigated experimentally and theoretically. Measurements show that, in contrast to conventional lasers, the threshold gain attains a…

We demonstrate lasing into counter-propagating modes of a ring cavity using a gas of cold atoms as a gain medium. The laser operates under the usual conditions of magneto-optical trapping with no additional fields. We characterize the…

Atomic Physics · Physics 2018-10-24 Balazs Megyeri , Graeme Harvie , Andreas Lampis , Jon Goldwin