摘要
Methane has been used as a nonlinear optical medium to produce tunable coherent vacuum ultraviolet and extreme ultraviolet radiation.A vibrational structure with a vibrational frequency of 820cm^(-1) was observed in a highly resolved third harmonic spectrum.This proved that third harmonic generation is an effective method to probe the higher excited states of molecular gases.
基金
Supported by the High Technology Program of Lasers(863-410)
the National Natural Science Foundation of China under Grant No.19584001.
