Probing Purcell enhancement and photon collection efficiency of InAs quantum dots at nodes of the cavity electric field

The interaction of excitonic transitions with confined photonic modes enables tests of quantum physics and design of efficient optoelectronic devices. Here we study how key metrics such as Purcell factor, beta-factor and collection efficiency are determined by the non-cavity modes which exist in real devices, taking the well-studied micropillar cavity as an example. Samples with dots at different positions in the cavity field allow us to quantify the effect of the non-cavity modes and show that the zero-phonon line and the phonon-assisted emission into the cavity mode HE11 is suppressed by positioning dots at the field node.