Phonon laser effect and Dicke–Hepp–Lieb superradiant phase transition in magnetic cantilever coupled to a Bose–Einstein condensate
Aranya B. Bhattacherjee, Tobias Brandes
We propose the possibility of a phonon laser by coupling a Bose–Einstein condensate to a nanomechanical cantilever with a magnetic tip. Due to the magnetic coupling, atomic spin flips induce cantilever motion, which can be used to produce a phonon laser. The system is described by the equivalent of the Jaynes–Cummings Hamiltonian. By controlling the number of atoms and the population inversion, one can obtain either a continuous wave or transient lasing. The two-body atom–atom interaction is also shown to coherently manipulate the lasing process. We also show that in the strong coupling limit, the same system can undergo a Dicke–Hepp–Lieb superradiant phase transition. Exotic phase diagrams can be obtained by tuning the two body atom–atom interaction.
arXiv:1209.3244•Canadian Journal of Physics•May 16, 2013•3 citations