Alexander Lvovsky

Abstract:

The generation of optical squeezed vacuum states by means of polarization self-rotation in rubidium vapor was reported. It was found that the experimental setup which involved in essence just a diode laser and a heated rubidium gas cell was easily scalable. Results showed that a squeezing of (0.85±0.05) dB was achieved.

Abstract:

Two closely spaced 778 nm, 4-ps pulses, two-photon resonant with the 5S-5D transition in Rb vapor generate a ground state grating, which later is excited by a similar third pulse, producing conical yoked superfluorescence echo on the 5S-6P, 420-nm transition. The intensity of this emission as a function of the relative delay between the leading excitation pulses is governed by the dynamics of Doppler dephasing and rephasing. This is the first observation of an echo effect induced by a spontaneous relaxation process.

Abstract:

We present systematic conceptual and experimental investigations of the bulk contribution to surface sum-frequency generation (SFG) from an isotropic medium. A practical method for the analysis of spectra obtained in a transmission geometry is presented which allows to estimate the bulk contribution in any future application. A systematic degeneracy due to the molecular nature of the material is found which makes a subtle interpretation of transmission experiments necessary. Practical consequences for the analysis of typical SFG spectra are discussed.