Experimental demonstration and modeling of near-infrared nonlinear third-order triple-photon generation stimulated over one mode

TL;DR

This paper reports the first experimental demonstration of stimulated near-infrared third-order triple-photon generation over one mode, with measurements aligning with a new theoretical model based on the nonlinear momentum operator.

Contribution

It presents the first experimental realization of stimulated TPG over one mode and develops a theoretical model to explain the observed photon generation.

Findings

Photon generation rate up to 2x10^-4 per pulse

Phase-matching at 1491 nm with modes at 1654 nm

Experimental results agree with the developed theoretical model

Abstract

Triple Photon Generation (TPG) is a third-order nonlinear optical interaction in which a photon, i.e. the pump, splits into three lower energy photons, i.e. modes 1, 2 and 3. The triplets possess different quantum signatures from those of photon pairs, with a strong interest in quantum information. In the present study, we performed the first experimental demonstration of TPG stimulated over one mode of the triplet, mode 1, the previous work on TPG concerning stimulation over two modes,2 and 3. The nonlinear medium is a KTiOPO4 crystal pumped in the picosecond regime (15 ps, 10 Hz) at a pump wavelength of 532 nm. The stimulation beam is emitted by a tunable optical parametric generator: the phase-matching was found at a stimulation wavelength of 1491 nm, the other two modes of the triplet being both at 1654 nm in orthogonal polarizations. Using superconducting nanowires single photon detectors, the measurement of the polarizations and wavelength signatures of the two generated modes are in full agreement with calculations. It has been possible to generate a total number of photons per pulse on modes 2 and 3 up to 2x10-4, which corresponds to the generation of 10-4 triplets per pulse, or 10-5 triplets per second since the repetition rate is equal to 10 Hz. We interpreted these results in the framework of a model we developed on the basis of the nonlinear momentum operator in the Heisenberg representation under the undepleted pump and stimulation approximation.