Shinji Kobayashi

Slab Co, Lasers Excited By All Solid State Rf Generators

Water-operated heat exchanger since line-narrowed outputs can be obtained maintaining the continuous wavelength tunability. In this paper, we demonstrate 10 GHz active frequency shift using a high-pressure CO, laser. The experimental apparatus is shown in Fig. 1. The main section of the system was an injection-locked high-pressure CO, laser with a gain volume of 1 X 1 X 30 cm’. The laser can operate at a pressure up to 10 atm. Then, the maximum input energy density was 1000 J/t. In addition to a main cavity consisting of a rear reflector (RR) and an output coupler (OC), a subcavity was constructed by the RR and a total reflector (TR). The RR was mounted on the laser tube in order to shorten the cavity length. The lengths of the main cavity and the subcavity were 95 cm and 105 cm, respectively. An A 0 frequency shifter instaIled in the subcavity was driven at a frequency of 40 MHz. The experiment was carried out at around the 1OP (20) line since no dispersive element for coarse tuning was used. Figure 2 shows the frequency shift as a function of the gate pulse width of the PC. The slope of 9.5 GHz/ ks agreed well with the value of 9.4 GHz/ks calculated from the round-trip frequency shift of 80 MHz and the round-trip time of 8.5 ns in the subcavity. The maximum frequency shift obtained was 9 GHz at a pressure of 8 atm. At higher pressures the maximum frequency shift was decreased by the reduction of the gain duration time although the gain bandwidth became wider. In order tu select other wavelength regions, we replaced the RR by a low-dispersive (50 lines/”) diffraction grating. The frequency shift was successfully obtained without degrading the tuning linearity and the maximum frequency shift. “Department of Physics, Science University of Tokyo, 1-3 Kagurazaka, Shinjyuku-ku, Tokyo 262, IAPAN