Time and spectrum-resolving mutiphoton correlator for 300-900 nm

TL;DR

This paper presents a sensitive spectrometer capable of time-resolved and multi-photon spectral correlation measurements in the visible range, with potential applications in quantum optics and medical imaging.

Contribution

A novel single-photon sensitive spectrometer combining a monochromator and avalanche diodes for high-resolution, time-resolved spectral measurements in the visible spectrum.

Findings

Achieves 110 ps time resolution

Spectral resolution of 2 nm per pixel

Compatible with commercial monochromators

Abstract

We demonstrate a single-photon sensitive spectrometer in the visible range, which allows us to perform time-resolved and multi-photon spectral correlation measurements. It is based on a monochromator composed of two gratings, collimation optics and an array of single photon avalanche diodes. The time resolution can reach $110$ ps and the spectral resolution is $2$ nm/pixel, limited by the design of the monochromator. This technique can easily be combined with commercial monochromators, and can be useful for joint spectrum measurements of two photons emitted in the process of parametric down conversion, as well as time-resolved spectrum measurements in optical coherence tomography or medical physics applications.