Integrated optical spectrum analyzer with internal gain

The first scanning integrated optical spectrum analyzer (IOSA) with resolution enhancement due to intracavity loss compensation in an amplifying Ti:Er:LiNbO/sub 3/-waveguide is reported. The active IOSA of about 1.423 GHz free spectral range has been diode-pumped at /spl lambda//sub p/=1479 nm (E/sub p//spl par/c) slightly below the lasing threshold at 1531 nm (P/sub p,th//spl cong/40 mW). Linear scanning of the cavity resonances has been achieved by driving the phase modulator (U/sub x//spl cong/10.4 V) with a sawtooth voltage. A finesse up to 205 has been achieved at /spl lambda//sub s//spl cong/1546 nm.>