论文简介 |
We propose an experimentally feasible method for enhancing the atom-field coupling as well as the ratio
between this coupling and dissipation (i.e., cooperativity) in an optical cavity. It exploits optical parametric
amplification to exponentially enhance the atom-cavity interaction and, hence, the cooperativity of the
system, with the squeezing-induced noise being completely eliminated. Consequently, the atom-cavity
system can be driven from the weak-coupling regime to the strong-coupling regime for modest squeezing
parameters, and even can achieve an effective cooperativity much larger than 100. Based on this, we further
demonstrate the generation of steady-state nearly maximal quantum entanglement. The resulting entanglement
infidelity (which quantifies the deviation of the actual state from a maximally entangled state) is
exponentially smaller than the lower bound on the infidelities obtained in other dissipative entanglement
preparations without applying squeezing. In principle, we can make an arbitrarily small infidelity. Our
generic method for enhancing atom-cavity interaction and cooperativities can be implemented in a wide
range of physical systems, and it can provide diverse applications for quantum information processing. |