Converting one photon into two via four-wave mixing in optical fibers

TL;DR

This paper analyzes four-wave mixing in optical fibers, demonstrating that tapered chalcogenide glass fibers can efficiently convert a single photon into a photon pair, advancing quantum information applications.

Contribution

It provides a detailed calculation showing enhanced single-photon to photon-pair conversion in tapered fibers, surpassing previous bulk and crystal sources.

Findings

Single-photon to photon-pair conversion probability of 0.1% in tapered fibers

Enhanced nonlinear optical effects at low light intensities in specialized fibers

Potential applications in quantum communication and entanglement generation

Abstract

Observing nonlinear optical quantum effects or implementing quantum information protocols using nonlinear optics requires moving to ever-smaller input light intensities. However, low light intensities generally mean weak optical nonlinearities, inadequate for many applications. Here we calculate the performance of four-wave mixing in various optical fibers for the case where one of the input beams is a single photon. We show that in tapered chalcogenide glass fibers (microwires) a single photon plus strong pump beam can produce a pair of photons with probability 0.1%, much higher than in previous work on bulk and waveguided crystal sources. Such a photon converter could be useful for creating large entangled photon states, for performing a loophole-free test of Bell's inequalities, and for quantum communication.