13 research outputs found
Cavity-Controlled Collective Scattering at the Recoil Limit
We study collective scattering with Bose-Einstein condensates interacting
with a high-finesse ring cavity. The condensate scatters the light of a
transverse pump beam superradiantly into modes which, in contrast to previous
experiments, are not determined by the geometrical shape of the condensate, but
specified by a resonant cavity mode. Moreover, since the recoil-shifted
frequency of the scattered light depends on the initial momentum of the
scattered fraction of the condensate, we show that it is possible to employ the
good resolution of the cavity as a filter selecting particular quantized
momentum states.Comment: 4 pages, 4 figure
Cavity-enhanced superradiant Rayleigh scattering with ultra-cold and Bose-Einstein condensed atoms
We report on the observation of collective atomic recoil lasing and
superradiant Rayleigh scattering with ultracold and Bose-Einstein condensed
atoms in an optical ring cavity. Both phenomena are based on instabilities
evoked by the collective interaction of light with cold atomic gases. This
publication clarifies the link between the two effects. The observation of
superradiant behavior with thermal clouds as hot as several tens of
proves that the phenomena are driven by the cooperative
dynamics of the atoms, which is strongly enhanced by the presence of the ring
cavity.Comment: 10 pages, 10 figure
Cavity-Controlled Collective Scattering at the Recoil Limit
We study collective scattering with Bose-Einstein condensates interacting
with a high-finesse ring cavity. The condensate scatters the light of a
transverse pump beam superradiantly into modes which, in contrast to previous
experiments, are not determined by the geometrical shape of the condensate, but
specified by a resonant cavity mode. Moreover, since the recoil-shifted
frequency of the scattered light depends on the initial momentum of the
scattered fraction of the condensate, we show that it is possible to employ the
good resolution of the cavity as a filter selecting particular quantized
momentum states.Comment: 4 pages, 4 figure
Collective scattering in an optical ring cavity
Ultrakalte Atome, welche mit den Moden eines optischen Resonators wechselwirken, stellen ein spannendes Objekt für das Studium kollektiver Phänomene dar. Vor wenigen Jahren konnte bereits der Zusammenhang zwischen superradianter Rayleighstreuung und dem kollektiven atomaren Rückstoßlaser hergestellt und der Beweis erbracht werden, dass beide auf dem gleichen Verstärkungsmechanismus beruhen. In dieser Arbeit wird darüber hinaus gezeigt, wie aufgrund der schmalen Resonatorlinienbreite die Besetzung äußerer Freiheitsgrade beeinflusst wird. Durch die Streuung von Photonen fester Frequenzen können die Atome nur bestimmte Impulsmoden besetzen. Dies ist der erste Schritt zur kohärenten Kontrolle der äußeren Freiheitsgrade ultrakalter Atome.Cold atoms that interact with a mode of an optical resonator constitute an interesting system for the study of collective phenomena. Some years ago, the link between superradiant Rayleigh scattering and the collective atomic recoil laser was demonstrated, showing that both effects are based upon the same gain mechanism. In this thesis, we show that the very narrow width of the cavity resonances influence the external degrees of freedom. Through the scattering of photons at a fixed frequency, atoms occupy only given momentum states. This is the first step towards the coherent control of the external degrees of freedom of cold atoms