Enhanced GeSn Microdisk Lasers Directly Released on Si

GeSn alloys are promising candidates for complementary metal-oxide-semiconductor-compatible, tunable lasers. Relaxation of residual compressive strain in epitaxial has recently shown promise improving the lasing performance. However, suspended device configuration that is thus far introduced to relax destined limit heat dissipation, hindering Herein demonstrated strain-free microdisk laser devices fully released on Si outperform canonical devices. This approach allows simultaneously limiting while offering excellent thermal conduction. Optical simulations confirm that, despite a relatively small refractive index contrast between and Si, optical confinement cavities superior conventional air. Moreover, indicate negligible temperature increase device. Conversely, increases substantially reaching, instance, 120 K at base 75 under employed pumping conditions. Such improvements enable increasing operation by ?40 reducing threshold 30%. lays groundwork implement new designs quest room lasers Si.