# Quantum correlation measurement with single photon avalanche diode arrays

**Authors:** Gur Lubin, Ron Tenne, Ivan Michel Antolovic, Edoardo Charbon, Claudio Bruschini, Dan Oron  
**arXiv:** [1910.01376](https://arxiv.org/abs/1910.01376)  
**Date:** 2019-10-03  
**Summary page:** https://www.summarizepaper.com/en/paper/1910.01376v1/

## Key points

- Temporal photon correlation measurement is important in quantum optics
- Single photon avalanche diode (SPAD) arrays have potential as high-performance detector arrays for quantum imaging and photon number resolving (PNR) experiments
- Researchers incorporated a novel on-chip SPAD array with 55% peak photon detection probability, low dark count rate, and crosstalk probability of 0.14% per detection in a confocal microscope
- This enables reliable measurements of second and third order photon correlations from a single quantum dot emitter
- The analysis overcomes inter-detector optical crosstalk background even though it is over an order of magnitude larger than the faint signal being measured
- The researchers showcase the vast application space of such an approach by implementing a super-resolution imaging method called quantum image scanning microscopy (Q-ISM)
- Q-ISM allows for sub-diffraction-limited spatial resolution imaging using entangled photons and can be used to image biological samples with high precision
- This study demonstrates the potential for SPAD arrays to revolutionize quantum correlation measurements and enable new applications in quantum imaging and PNR experiments that were not possible before.

## Summary

In the field of quantum optics, temporal photon correlation measurement is a crucial tool for probing the quantum properties of light. Recent progress in single photon avalanche diode (SPAD) array technology has highlighted their potential as high-performance detector arrays for quantum imaging and photon number resolving (PNR) experiments. In a new study, published in Optics Express, researchers demonstrate this potential by incorporating a novel on-chip SPAD array with 55% peak photon detection probability, low dark count rate and crosstalk probability of 0.14% per detection in a confocal microscope. This enables reliable measurements of second and third order photon correlations from a single quantum dot emitter. The analysis overcomes the inter-detector optical crosstalk background even though it is over an order of magnitude larger than the faint signal being measured. The researchers also showcase the vast application space of such an approach by implementing a recently introduced super-resolution imaging method called quantum image scanning microscopy (Q-ISM). This technique allows for sub-diffraction-limited spatial resolution imaging using entangled photons and can be used to image biological samples with high precision. Overall, this study demonstrates the potential for SPAD arrays to revolutionize quantum correlation measurements and enable new applications in quantum imaging and PNR experiments that were not possible before.