A QCSE tuned laser with uniform frequency modulation response for use in microwave photonics

Conventional semiconductor lasers tuned by the carrier-induced effect (CIE) suffer from intrinsically non-uniform optical frequency modulation (FM) response due to the associated thermal effect. Electric field effect tuned lasers involving no current injection, offer intrinsically uniform FM response. We report the first post-growth band-gap engineered, quantum-confined Stark effect (QCSE) tuned two-section ridge waveguide laser, having the widest and most uniform frequency modulation bandwidth (30 kHz to 6 GHz /spl plusmn/3 dB) yet reported for field effect tuned lasers. The uniform FM response is independent of laser output power, and residual intensity modulation is less than 5% for 4.5 GHz peak frequency deviation.