Dynamic characteristics and noise modelling of directly modulated quantum well-dots microdisk lasers on silicon

The small-signal amplitude modulation, threshold, and spectral characteristics of microdisk lasers with InGaAs/GaAs quantum well-dots active region were studied jointly with the spectral and threshold parameters of edge-emitting lasers made from the same epitaxial heterostructure. Using the obtained material parameters, the relative intensity noise of the microdisk lasers was calculated as a function of the bias current and side-mode suppression ratio. It is shown that the integral noise is low enough for error-free optical data transmission with the maximum possible bitrate limited by the microdisk modulation bandwidth, if the bias current is above 1.7× threshold current (for side mode suppression ratio > 20 dB).

Temperature stability of small-signal modulation response of WGM microlasers with InGaAs/GaAs quantum well-dots in the active region

In this paper, results are presented on III-V quantum well dot microring diode lasers tested at elevated temperatures. To the best of our knowledge, the first uncooled microdisk lasers with diameter of 40 μm with 3-dB bandwidth above 2 GHz at 55°C are demonstrated.

Output power of multilayered InGaAs/GaAs quantum well-dot microdisk lasers

We studied the output optical power of microdisk lasers with InGaAs/GaAs quantum dots active region. An increase in the number of layers in the active region in the waveguide from 2 to 6 leads to increase in the peak output optical power due probably to increase of the gain. We also observe a corresponding increase of the threshold current due to the increase on the transparence current. The maximal optical power is achieved for structure with 6 layers at approximately 60 mA injection current. Further increase of the number of the QD layers to 10 results in increase of the threshold current and sudden drop of the output power.