High-temperature continuous wave operation (up to 100°C) of InAs/InGaAs quantum dot electrically injected microdisk lasers

In this work, electrically-injected microdisk lasers with diameter varied from 15 to 31μm based on an InAs/InGaAs QD active region have been fabricated and tested in continuous wave regime. At room temperature, lasing is achieved at wavelength around 1.26…1.27 μm with threshold current density about 900 A/cm2. Specific series resistance is estimated to be about 10-4 Ohm•cm2. The lasers were tested at elevated temperatures. Lasing is achieved up to 100°C with threshold current of 13.8mA and lasing wavelength of 1304nm in device with 31μm diameter. To the best of our knowledge, this is the highest CW lasing temperature and the longest lasing wavelength ever reported for injection QD microdisk/microring lasers on GaAs substrates. Emission spectrum demonstrates single-mode lasing with side mode suppression ration of 24dB and dominant mode linewidth of 35pm. The far field radiation pattern demonstrates two narrow maxima off the disk plane. A combination of device characteristics achieved (low threshold, long wavelength, operation at elevated temperatures) makes them suitable for application in future optoelectronic circuits for optical interconnect systems.