Cooling many particles to very low temperatures
  In a recent paper [Beige, Knight, and Vitiello, quant-ph/0404160], we showed that a large number N of particles can be cooled very efficiently using a bichromatic interaction. The particles should be excited by red-detuned laser fields while coupling to the quantized field mode inside a resonant and leaky optical cavity. When the coupling constants are for all particles the same, a collective behavior can be generated and the cooling rate can be as large as square root of N times the single-particle coupling constants. Here we study the algebraic structure of the dynamics and the origin of the collective cooling process in more detail. 
Almut Beige, Peter L. Knight, and Giuseppe Vitiello