Cooling through optimal control of quantum evolution

Armin Rahmani, Takuya Kitagawa, Eugene Demler, Claudio Chamon
2013 Physical Review A. Atomic, Molecular, and Optical Physics  
Nonadiabatic unitary evolution with tailored time-dependent Hamiltonians can prepare systems of cold atomic gases with various desired properties. For a system of two one-dimensional quasicondensates coupled with a time-varying tunneling amplitude, we show that the optimal protocol, for maximizing any figure of merit in a given time, is bang-bang, i.e., the coupling alternates between only two values through a sequence of sudden quenches. Minimizing the energy of one of the quasicondensates
more » ... such nonadiabatic protocols, and then decoupling it at the end of the process, can result in effective cooling beyond the current state of the art. Our cooling method can be potentially applied to arbitrary systems through an integration of the experiment with simulated annealing computations.
doi:10.1103/physreva.87.043607 fatcat:t5d32jbvg5hsbgbjgdgrjy5mbm