Room temperature optically pumped GeSn microdisk lasers

Abstract

GeSn alloys are promising materials for light emitters monolithically grown on silicon. In this work, we demonstrate room temperature (RT) lasing in a GeSn hetero-structure with 17.2% of Sn. We report a threshold of 3.27 MW cm−2 at 305 K with peak emission at 353 meV. We ascribe these improvements to a higher tin concentration in the GeSn active layer with lower Sn content barriers on each side and to a better thermal dissipation provided by an adapted pedestal architecture beneath the GeSn micro-disk. This outcome is a major milestone for a fully integrated group-IV semiconductor laser on Si.

Room Temperature Lasing in GeSn Microdisks Enabled by Strain Engineering

“…The inset shows the lasing mode linewidth (full width at half maximum) as a function of the pump power that was extracted from emission spectra in (d) at 300 K. We observe a clear linewidth reduction by a factor of around two at threshold. for 17.2 at% Sn layer [17] and at temperatures below 250 K for 16.9 at%Sn [16] than those measured for both structures here. Also intriguing is the difference in the laser emission, that is single-mode in ref.…”

“…[15] like the removal of interface defects. [16,17] As discussed in the introduction the tensile strain promotes the CB directness and shifts the laser transition from Γ-HH to Γ-LH. As discussed above this is expected to reduce the carrier density at threshold.…”

Impact of strain engineering and Sn content on GeSn heterostructured nanomaterials for nanoelectronics and photonic devices

“…37b). 137 Anas ElBaz et al deposited the GeSn layer with 5.4% Sn content. They employed E-lithography to fabricate 9 mm of a microdisk, then surrounded it by a 350 nm SiN x stressor layer to relax the GeSn layer and reduce dislocations.…”

Synthesis of Ge1−xSnx nanoparticles under non-inert conditions

“…5 Examples of optoelectronic devices have already been made with Ge 1−x Sn x films, such as lasers and LEDs, 6 where room temperature lasing has been achieved recently in Ge 1−x Sn x microdisks with 17% Sn. 7 The magnitude and type of the bandgap of Ge 1−x Sn x cannot only be controlled by the Sn concentration since these properties also depend on the particle size when in the form of nanoparticles. A decreasing particle size will increase the bandgap energy due to the quantum confinement effect.…”

“…5 Examples of optoelectronic devices have already been made with Ge 1− x Sn x films, such as lasers and LEDs, 6 where room temperature lasing has been achieved recently in Ge 1− x Sn x microdisks with 17% Sn. 7…”