System and method for quantum absorption spectroscopy

Abstract

The quantum optical system changes a phase of quantum interference occurring between a plurality of physical processes, in each of which a quantum entangled photon pair of a signal photon and an idler photon is generated. Each of a plurality of pixels outputs a detection signal of the signal photon in a state where a sample is arranged in an optical path of the idler photon. A processor calculates an absorption spectroscopy characteristic based on an interferogram indicating a variation in a signal intensity acquired from each of the plurality of pixels in accordance with the change in the phase of the quantum interference. The processor: applies a processing to reduce phase difference of the interferogram among the plurality of pixels; spatially integrates, over the plurality of pixels, the interferogram having gone through the processing to reduce phase differences; and calculates the absorption spectroscopy characteristic based on the integrated interferogram.