Produção Nacional
Two-photon cooling of magnesium atoms
2005; American Physical Society; Volume: 72; Issue: 5 Linguagem: Inglês
10.1103/physreva.72.051403
ISSN1538-4446
AutoresNicola Malossi, S. Damkjær, Per Lunnemann, L Jacobsen, L. Kindt, Sébastien Sauge, J. W. Thomsen, Flávio C. Cruz, M. Allegrini, E. Arimondo,
Tópico(s)Quantum optics and atomic interactions
ResumoA two-photon mechanism for cooling atoms below the Doppler temperature is analyzed. We consider the magnesium ladder system $(3{s}^{2})^{1}S_{0}\ensuremath{\rightarrow}(3s3p)^{1}P_{1}$ at $285.2\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ followed by the $(3s3p)^{1}P_{1}\ensuremath{\rightarrow}(3s3d)^{1}D_{2}$ transition at $880.7\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$. For the ladder system quantum coherence effects may become important. Combined with the basic two-level Doppler cooling process this allows for reduction of the atomic sample temperature by more than a factor of 10 over a broad frequency range. First experimental evidence for the two-photon cooling process is presented and compared to model calculations. Agreement between theory and experiment is excellent. In addition, by properly choosing the Rabi frequencies of the two optical transitions a velocity independent atomic dark state is observed.
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