APPLICATION OF DIODE-LASERS AS A SPECTROSCOPIC TOOL AT 670 NM

For optical experiments at the resonance wavelength of lithium atoms a t 670 nm an external cavity diode laser was set up. The cavity consist ed of the diode, a collimating lens and a diffraction grating used in Littrow geometry. At an optical length of 20 mm a continuously tunable range of 56 GHz was obtained using a diode with an anti-reflection co ating on the output facet. 30 GHz were reached using a commercial diod e as is. Laser induced fluorescence experiments on an atomic beam demo nstrate the spectroscopic usability and put an upper limit of 25 MHz o n the laser linewidth.