HIGH-GAIN ULTRAVIOLET CU-II LASER IN A SEGMENTED HOLLOW-CATHODE DISCHARGE

We report measurements of the discharge and laser characteristics of a n ultraviolet (UV) copper ion laser radiating on the 248.6- and 270.3- nm transitions. Our 50-cm active length laser operates in a high-volta ge segmented hollow cathode discharge with Brewster windows and extern al mirrors, The lowest threshold currents were 7.3 and 5.6 A for the a bove transitions, respectively, The threshold current was found to inc rease with decreasing active length, We obtained superior gain charact eristics (to 11.2 and 8.8%/m gain for the 248.6- and 270.3-nm transiti ons, respectively, at 0.3 A/cm linear current density) compared with p revious studies on UV Cu ion lasers in conventional hollow cathode dis charges.