Focused ion beam etching for the fabrication of micropillar microcavities made of III-V semiconductor materials

The authors demonstrate a simple approach for the construction of single photon sources utilizing focused ion beam (FIB) etching, a maskless fabrication technique. Here they use FIB with gas-assisted etching to fabricate micropillar microcavities from a GaAs∕AlGaAs distributed Bragg reflector planar cavity containing self-assembled InAs quantum dots. Using a 1.5μm square pillar, they demonstrate a single photon source where the two photon emission is suppressed by a factor of 3.8. They believe this to be the first example of a FIB fabricated pillar single photon source.