We describe the operation of two GaN-based diode lasers for the laser
spectroscopy of gallium at 403 nm and 417 nm. Their use in an external cavity
configuration enabled the investigation of absorption spectroscopy in a gallium
hollow cathode. We have analyzed the Doppler broadened profiles accounting for
hyperfine and isotope structure and extracting both the temperature and
densities of the neutral atomic sample produced in the glow discharge. We have
also built a setup to produce a thermal atomic beam of gallium. Using the
GaN-based diode lasers we have studied the laser induced fluorescence and
hyperfine resolved spectra of gallium.Comment: 10 pages, 7 figure