SPIE Quantum Technologies

Structural dependence of antibunching and fluorescence lifetime

Madhura Ghosh Dastidar, Praveen Hegde, Immanuel Thekkooden, Vidya Praveen Bhallamudi

Published Jun 10, 2024• 0 citations

Abstract

The rapid growth of quantum technologies has driven the development of quantum defects for both single photon sources as well as for spin qubit and sensor applications. These artificial atoms in wide bandgap solid-state materials such as diamond and hBN offer the possibility of a truly quantum deterministic source. These single photon emitting quantum defects exhibit antibunching that can be quantified by performing the Hanbury-Brown Twiss (HBT) experiment. The HBT experiment allows one to evaluate the second-order autocorrelation (g(2)(τ )) function, which is a central measure in determining the quality of single photon emission. To enhance the various emission parameters such as intensity, wavelength, and directionality from these defects the development of photonic structures become essential. Here, we study single photon emission from a diamond nanopillar array containing Nitrogen Vacancy (NV) centers. We spatially map the g(2)(τ ) function and radiative lifetimes in these samples and correlate the two quantities. Crucially, we observe that the measured antibunching varies as a function of position of the objective relative to the nanopillar, even across the same pillar. This likely shows the dependence of the apparent antibunching to the angle of excitation and detection in such photonic structures. Our results highlight the importance of structural and geometric factors in g(2)(τ ) measurements of emitters, especially when embedded in photonic structures. These should be carefully understood in evaluating the quality of the single photon sources.

DOI: 10.1117/12.3016497

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