Thermal characterization of electrically injected GaN-based microdisk lasers on Si

GaN-based microdisk lasers grown on Si have a wide application prospect in communication and Si photonics. However, the relatively large threshold current and thermal resistance often cause a very high junction temperature, which severely affects the device performance. Here we analyzed the thermal characteristics of GaN-based microdisk lasers grown on Si substrates. According to the simulation results, we have significantly reduced the threshold current and junction temperature by reducing the current injection area and device size, respectively. As a result, continuous wave electrically injected lasing has been achieved at room temperature for both microring and microdisk lasers grown on Si.