Laser cooling and trapping of atoms

Laser cooling techniques: standard and alternated optical molasses

“…There are basically two kinds of forces exerted on an atomic system due to interaction with radiation: spontaneous and dipole forces [7,11]. The spontaneous force originates from the momentum transferred to the atom during the photon absorption or emission processes.…”

“…The first term in the denominator of equation (2) is velocity dependent and, as the atom slows down, the Doppler shift ω D = −k ·ṙ brings it out of the resonance condition, lowering the force magnitude. In order to reach the deceleration that changes the atomic speed by hundreds of m/s, it is necessary to compensate the Doppler shift to keep ∆ + ω D << Γ, either modifying ω D or ∆ [11].…”

Magneto-optical Trap: Fundamentals and Realization

“…In this paper we briefly review the essential cooling mechanisms related to the MOT, including both Doppler and sub-Doppler ones, and present our trap with some examples of the results. There are several excellent sources discussing many aspects of laser cooling at length [2,[23][24][25][26][27], our introductory treatment given below is based and benefits from these works.…”

Scattering theory of multilevel atoms interacting with arbitrary radiation fields

“…The two-level model of atoms interacting with light fields [1] has often been used to explore optical cooling mechanisms [2][3][4]. Its inherent simplicity-the atom has one ground state and one excited state-makes the resulting models amenable to analysis, but also suppresses mechanisms [5] that, in the appropriate parameter regimes, dominate the interaction.…”