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 31 mu m 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 mu m with threshold current density about 900 A/cm(2). Specific series resistance is estimated to be about 10(-4) Ohm.cm(2). The lasers were tested at elevated temperatures. Lasing is achieved up to 100 degrees C with threshold current of 13.8mA and lasing wavelength of 1304nm in device with 31 mu m 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.