HIGH RESOLUTION FOUR-WAVE MIXING SPECTROSCOPY OF MARROW RKSONANCES IN DOPPLER BROADENED SYSTEMS

袁石, 吴金辉, 高锦岳

Rama K. Raj, E. Köster, Q. F. Gao +3 more

Rama K. Raj, E. Köster, Qinghua Gao +3 more

Jean-Luc Boulnois

CW phase conjugation on the ν3 vibrational bands of SF6 and OsO4 is demonstrated as a means of investigation in high resolution spectroscopy through resonant degenerate four-wave mixing at 10.6 µm by using a stable low power CO2 laser operating on the P(18), P(16), P(12) lines respectively. Peak reflectivities of 3.8 10-3 are measured in SF6. They only reach 0.34 10-3 in OsO4. Phase conjugate spectra with 2 MHz, namely sub-Doppler resolutions, are compared with simultaneous recordings of the saturated-absorption spectra over a 80 MHz bandwidth. The saturation splitting encountered on a one-photon transition in SF6 is also analysed in terms of pressure broadening and pump imbalance.

Panming Fu, 中国科学院物理研究所

We have studied the saturation effect of degenerate four-wave mixing in Doppler-broadened two-level system. A set of recurrent formula which is suitable for numerical analysis is derived and applied to calculate the lineshape of four-wave mixing signal in the weak saturation region. The results show that a double-peak structure appears at the line center as the intensity of the incident light increases.

J. L. Oudar

The use of multiresonant four-wave mixing processes in solid-state spectroscopy is analyzed in detail. Specific information on the excited states of solids can be obtained from such techniques, including the reduction of inhomogeneous broadening, study of transitions between excited states, determination of ultrafast relaxation times through measurements in the frequency domain.