An atom laser for quantum-atom optics

Chun-Chia Chen, Shayne Bennetts, Rodrigo González Escudero +2 more

Keith R. Burnett

A holy grail for physicists working in atom optics has long been an atom laser – a coherent beam in which all the atoms are in the same quantum state and are all travelling in the same direction with the same speed. Just as lasers have made optical techniques the preferred route for an extraordinary range of science and technology, an atom laser would give a powerful boost to atom optics and its applications, including atom interferometry and the laser-guided deposition of atoms. Although there is an active debate about what will constitute the observation of an atom laser, Wolfgang Ketterle and co-workers at the Massachusetts Institute of Technology in the US have demonstrated what some physicists agree is a pulsed atom laser.

Zhao Jian-Gang, Sun Chang-Yong, Meng Xiang-Guo +2 more

The squeezing properties of atom laser are investigated with and without rotating-wave approximation by means of quantum theory in the system of optical field interacting with Bose-Einstein condensate of two-level atoms. The influences of the atomic eigenfrequency, the interaction intensity between optical field and atoms，the initial squeezing factor of optical field and the virtual photon field on the squeezing properties are discussed. The results show that two quadrature components of atom laser can be squeezed periodically. The quantum Rabi frequency and the collapse and revival frequency of atom laser fluctuation depend on the atomic eigenfrequency and the interaction intensity between optical field and atoms respectively. When the initial squeezing factor of optical field increases and the virtual photon field is considered, the degree of squeezing of the atom laser also increases.

David Guéry-Odelin

Tobias Kramer, Mirta Rodríquez Pinilla, Christian Bracher

Прудников Олег Николаевич, А. В. Тайченачев, Valeriy I. Yudin +1 more

The possible deep laser cooling of 24 Mg atoms in a deep optical lattice in the presence of an additional pumping field resonant to the narrow 3 s 3 s 1 S 0 → 3 s 3 p 3 P 1 (λ = 457 nm) optical transition is studied. Two quantum models of the laser cooling of atoms in the optical trap are compared. One is based on the direct numerical solution to the kinetic quantum equation for an atomic density matrix; it considers both optical pumping and quantum recoil effects during interaction between the atoms and field photons. The second, simplified model is based on decomposing the states of the atoms over the levels of vibration in the optical trap and analyzing the evolution of these states. The comparison allows derivation of optical field parameters (pumping field intensity and detuning) that ensure cooling of the atoms to minimal energies. The conditions for fast laser cooling in an optical trap are found.