Time-dependent Mandel Q parameter analysis for a hexagonal boron nitride single photon source
Callum Jones, Jolly Xavier, Samir Vartabi Kashanian, Minh Nguyen, Igor Aharonovich, Frank Vollmer
Abstract
The time-dependent Mandel Q parameter, Q ( T ), provides a measure of photon number variance for a light source as a function of integration time. Here, we use Q ( T ) to characterise single photon emission from a quantum emitter in hexagonal boron nitride (hBN). Under pulsed excitation a negative Q parameter was measured, indicating photon antibunching at an integration time of 100 ns. For larger integration times Q is positive and the photon statistics become super-Poissonian, and we show by comparison with a Monte Carlo simulation for a three-level emitter that this is consistent with the effect of a metastable shelving state. Looking towards technological applications for hBN single photon sources, we propose that Q ( T ) provides valuable information on the intensity stability of single photon emission. This is useful in addition to the commonly used g (2) ( τ ) function for the complete characterisation of a hBN emitter.