Thermal and high speed modulation characteristics for AlGaInAs/InP microdisk lasers

Thermal and high speed modulation characteristics are investigated for a unidirectional-emission microdisk laser with a radius of 7 μm surrounded by BCB-cladding layer, with a threshold current of 1.5 mA at the temperature of 287 K. The lasing spectra under different widths of pulsed current are measured to characterize the temperature rise during the pulse period, and the thermal distribution in the microdisk laser is simulated by the finite-element modeling technique. A temperature rise of 25 K is estimated for the microdisk laser biased at 20 mA. Furthermore, small signal modulation response with 3dB bandwidth up to 20 GHz is obtained for the microdisk laser at the biasing current of 18 mA, and eye-diagrams at the modulation bit rates of 20, 25, and 30 GHz are also measured at the temperature of 287 K.