Single-frequency cw injection heterolaser tunable by an external dispersive resonator

An investigation was made of the spectral composition of the radiation emitted from a cw stripe AlGaAs–GaAs injection heterolaser operating at room temperature in an external dispersive resonator. Narrow-band (Δλ≤0.15 nm) stimulated emission with an output power up to 20 mW was obtained. The output radiation was tunable in a range of ~10 nm centered on the wavelength of 884 nm and in this case the maximum cw single-frequency power was 4 mW. Excitation of several longitudinal external-resonator modes (within the limits of the narrow emission band) was accompanied by rf intensity fluctuations consisting of mode beats (250–500 MHz) and a noise band at much lower frequencies (30–100 MHz).