Spectroscopy of alkali atoms in hollow-cathode discharge lamps using diode lasers

We report on experiments in which alkali metals were probed in (commercial) hollow-cathode discharge lamps, using simple semiconductor diode lasers. A variety of spectroscopic techniques have been employed to demonstrate the versatility of the set-up, including Doppler- limited absorption, fluorescence and optogalvanic spectroscopies, and Doppler-free polarization spectroscopy.