[OPTICAL REVIEW Vol. 7, No. 1 (2000) 18-21]

Effect of Photo-Induced Periodic Gain Structure on Oscillation Power and Tunability in Polymer Dye Laser

Takanori KEMANAI,1 Satoshi TANAKA,1* Seiichiro HAYAKAWA2 and Heihachi SATO1

1Department of Electrical Engineering, National Defense Academy, 1-10-20, Hashirimizu, Yokosuka, 239-8686 Japan, 2Mitsubishi Chemical Corporation, 8-3-1, Chuo, Ami, Inashiki, Ibaraki, 300-0332 Japan

(Received August 10, 1999; Accepted November 25, 1999)

Pumping dye-doped organic polymer by interference pattern of a frequency-doubled Nd:YAG 532 nm laser to induce a periodic gain-structure and confining it within a stable optical resonator, the oscillation output can be effectively enhanced in comparison with either that of uniform irradiation, i.e., pumping, or of distributed feedback (DFB) operation, and the oscillation wavelength becomes tunable by adjusting the period of the interference pattern. Using Rhodamine-B as a dopant over the range from 200 to 1000 ppm, the oscillation output was enhanced by~10 dB, which was larger than the output of the uniform irradiation and was~30% greater than the DFB scheme. Moreover, changing the period of the interference pattern by adjusting the setting angle of the Köster prism enables us to vary the oscillation wavelength around 600 nm.

Key words : dye laser, tunable laser, periodic gain structure, organic polymer, polymer dye laser