Mechanisms for Lasing with Cold Atoms as the Gain Medium

Abstract

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 measure an output power of up to 300 microW and present the main properties of these different lasers in each regime.

Linear and nonlinear Rabi oscillations of a two-level system resonantly coupled to an Anderson-localized mode

“…In terms of perspectives, this work opens further the way to various applications. For instance, sidebands resulting from the DSE were proposed to achieve coherent amplification [24] and could be used to achieve new random laser sources [35,36]. Anderson-localized modes can also be externally tuned by local modifications of the medium [16,37].…”

“…Among them, NPNMC was recently achieved between localized modes and nano-emitters [20][21][22][23], opening a new paradigm in the field of cQED. In contrast, DSE was proposed as a coherent amplification mechanism in cold-atom clouds [24]. Nevertheless, in such disordered systems, since atoms provide for the amplifcation their scattering strengh is very weak.…”

A quasi-continuous superradiant Raman laser with < 1 intracavity photon

“…Semiconductor microcavity lasers have very high cavity decay rates due to their small size, and have also attempted to enter the bad-cavity regime for the benefits of low threshold lasing, but have to the best of our knowledge, not realized / ⊥ > 1 [20]. Previous related experiments with cold-atom Raman lasers also operated in the superradiant limit [26][27][28], but did not study the spectral properties of the light in detail and operated with large intracavity photon numbers M c 1.…”

Light trapping in high-density ultracold atomic gases for quantum memory applications

“…For much higher atomic densities, such that kl ∼ 1, light scattering enters the so called strong localization regime. In this case, recurrent light scattering can lead to formation of long lived atomic-photonic excitations which are currently under investigation as possible quantum memories, in searches for Anderson localization of light [23][24][25][26][27], development of atomic-physics based random lasers [28,29], and for studies of single and multiple photon cooperative scattering [30,31].…”