High Precision Level Splitting Measurements with Picosecond Light Pulses from an Injection Laser

Abstract

Modulated pumping^{1, 2} is a well-known principal in high-resolution spectroscopy and can be used to create atomic coherence between close lying or even degenerate atomic or molecular states and allows to measure energy splittings between adjacent states³. In this context the possibility of optical pumping by a periodic pulse train has been mentioned by several authors⁴. So far, however, its potentiality and ability for quantitative measurements has only scarcely been employed.