Abstract

The reason macroscopically separated superpositions of quantum states are not normally observable is that dissipation and coupling to the environment lead to a fast destruction of the quantum coherence between these states. In cavity QED, dissipation can be kept to a minimum due to the recent progress in microwave technology utilizing resonators with quality factors as high as Q = 3 × 10¹⁰, with corresponding photon lifetimes in the order of milliseconds. In addition, spontaneous emission can largely be turned off in this regime by the use of closed cavities and circular Rydberg states.

© 1996 Optical Society of America