High-quality micropillar cavities were grown using molecular-beam epitaxy. Stable continuous-wave lasing at room temperature was demonstrated for microlasers with semiconductor and hybrid output mirrors. At 300 K, single-mode lasing was demonstrated for micropillars with a diameter of 5 μm at a wavelength of 960 nm, with a minimum lasing threshold of ∼1.2 mW and the quality-factor at threshold exceeding 8000.
Babichev et al. (Mon,) studied this question.