研究了四能级系统的超快调制光谱(UMSFS)中泵浦光为窄带或宽带的情形,发现它们对能级差的测量都可以达到消除多普勒增宽的精度。在符合拍频条件时, 能级差可以超出激光线宽,其测量精度可达到与激光线宽同一数量级。

The ultrafast modulation spectroscopy of a four-level system (UMSFS) has been studied in which the linewidths of the pump beams are either narrow or broad and it was found that for both cases a Doppler-free precision in the measurement of the energy-level difference can be achieved. In the condition that a beating occurs, the energy-level difference could exceed the laser linewidth, and the measurement accuracy could reach the same order of magnitude as the laser linewidth.