PR_29 Photon-Pair Generation using Coupled Silicon Microring Resonators (1201308-PO)

The physical principles of entangled photon-pair generation in coupled silicon microring resonators were studied theoretically and experimentally. Summary of a Project Outcomes report of research funded by the National Science Foundation under Project Number 1201308.

PR_34 Improved Photon-Pair Generation using Silicon Photonic Micro-resonators (1640968-Y1)

We focus on the development of key building blocks for entangled photon-pair generation using microchips that are cost-effective, compact, energy efficient and leverages modern micro-fabrication platforms such as silicon photonics. Summary of a Project Outcomes report of research funded by the U.S. National Science Foundation under Project Number 1640968 (Year 1).

PR37 An Alternative Strategy for Photon-Pair Generation using Integrated Photonics on Silicon Wafers (1640968-Y4)

Research activities include the design, fabrication and poling of a spontaneous parametric down-conversion (SPDC) waveguide in periodically-poled thin-film lithium niobate SPDC device, and measurements of photon-pair generation in it. Summary of a Project Outcomes report of research funded by the U.S. National Science Foundation under Project Number 1640968 (Year 4).

Photon-Pair Generation from Chip-Scale Cs Atomic Vapor Cell

The realization of a narrowband photonic quantum source based on a chip-scale atomic device is considered essential in the practical development of photonic quantum information science and technology. In this study, we present the first step toward the development of a photon-pair source based on a microfabricated chip-scale Cs atomic vapor cell. Time-correlated photon pairs from the millimeter-scale Cs vapor cell are emitted via the spontaneous four-wave mixing process of the cascade-type 6S1/2–6P3/2–8S1/2 transition of 133Cs. The maximum normalized cross-correlation value between the signal and idler photons is measured as 622(8) under a weak pump power of 10 mW. Our photon source violates the Cauchy–Schwartz inequality by a factor of >105. We believe that our approach has very important applications in the context of realizing practical scalable quantum networks based on atom–photon interactions.

Frequency and polarization emission properties of a photon-pair source based on a photonic crystal fiber

In this work, we experimentally demonstrate a photon-pair source with correlations in the frequency and polarization degrees of freedom. We base our source on the spontaneous four-wave mixing (SFWM) process in a photonic crystal fiber. We show theoretically that the two-photon state is the coherent superposition of up to six distinct SFWM processes, each corresponding to a distinct combination of polarizations for the four waves involved and giving rise to an energy-conserving pair of peaks. Our experimental measurements, both in terms of single and coincidence counts, confirm the presence of these pairs of peaks, while we also present related numerical simulations with excellent experiment-theory agreement. We explicitly show how the pump frequency and polarization may be used to effectively control the signal-idler photon-pair properties, defining which of the six processes can participate in the overall two-photon state and at which optical frequencies. We analyze the signal-idler correlations in frequency and polarization, and in terms of fiber characterization, we input the SFWM-peak experimental data into a genetic algorithm which successfully predicts the values of the parameters that characterize the fiber cross section, as well as predict the particular SFWM process associated with a given pair of peaks. We believe our work will help advance the exploitation of photon-pair correlations in the frequency and polarization degrees of freedom.