Single Photon Approach for Chirality Sensing

We developed a high sensitivity optical sensor for circular birefringence using a heralded photon source. The sensor can be employed for chirality measurements and, being based on single photons, can be exploited for fragile biological sample or in metrological applications where the light intensity must be kept as low as possible. We found the best operational condition; then, we calibrated the sensor and tested its performance up to a very long acquisition time, obtaining excellent stability and a sub-ppm birefringence detection limit (for a 100 mu m sample), thus paving the way for fundamental physics test as well.

Automated summary

We have developed a highly sensitive optical sensor for circular birefringence using a heralded photon source. This sensor can be utilized for chirality measurements and is suitable for delicate biological samples or metrological applications that require low light intensity. Through finding the optimal operational condition, calibrating the sensor, and testing its performance over a long acquisition time, we achieved excellent stability and a sub-ppm birefringence detection limit (for a 100 μm sample), which also opens up possibilities for fundamental physics tests.