Quantum Fluctuations of a Cavity QED System with Periodic Potential

Benjamin Lev, Sarang Gopalakrishnan, Paul M. Goldbart

Joseph E. Reiner, Frank Dimler, Luis A. Orozco

Doppler and transit broadening effects inherent in a thermal atomic beam reduce the size of quantum fluctuations in a cavity QED system. A cold continuous atomic beam would reduce these effects, but would not eliminate the different atom–field couplings associated with the random distribution of atoms throughout the cavity. We present results that describe the effect that this has on quantum fluctuations and how it could be used to improve future studies on the fluctuations from a cavity QED system. We also report on experimental progress towards a continuous cold atom source.

Jonathan Simon

Liangwei Wang, Jing Shi

Squeezed vacuum, as a nonclassical field, has many interesting properties and results in many potential applications for quantum measurement and information processing.Here, we investigate a single atom-cavity quantum electrodynamics (QED) system driven by a broadband squeezed vacuum.In the presence of the atom, we show that both the mean photon number and the quantum fluctuations of photons in the cavity undergo a significant depletion due to the additional transition pathways generated by the atom-cavity interaction.By measuring these features, one can detect the existence of atoms in the cavity.We also show that two-photon excitation can be significantly suppressed by the quantum destructive interference when the squeezing parameter is very small.These results presented here are helpful in understanding the quantum nature of the broadband squeezed vacuum.

Perry R. Rice, Mambwe Mumba, Dyan L. Jones