Quantum diffraction unlimited protocol for single-photon fluorophores

Achieving higher resolution scales in optical microscopy allow a more rigorous investigation into the detailed components of cell systems. This higher resolution is typically achieved through super-resolution techniques utilizing methods inside the wave-like nature of light such as point spread function shaping and fluorophore switching. We wish to leverage both particle-like and wave-like natures of light to make a diffraction unlimited protocol. Our protocol uses the well known Hanbury Brown and Twiss (HBT) apparatus in combination with a customized second-order cross-correlation protocol. By performing least squares fitting of the HBT and intensity measurements we obtain diffraction unlimited localization for two particles of unknown relative brightness from few measurement locations. Our results show super-resolution enhancement by an order of magnitude after 5000 detection lifetimes.