Hole whispering gallery laser of photonic quantum ring

We report on the first observation of "hole" whispering gallery lasers from semiconductor microcavities with three dimensional optical confinement, with thresholds potentially reducible to micro-to-nano ampere regimes If the device size grows over a critical diameter, the quantum ring whispering gallery then begins to disappear. However, cooperative small hole laser arrays, exhibiting photonic crystal structure properties, avoid the criticality and open a possibility of constructing practical high-density electro-pumped emitter arrays.