Frequency Multiplexing for Quasi-Deterministic Heralded Single-Photon Sources

In a new paper, “Frequency Multiplexing for Quasi-Deterministic Heralded Single-Photon Sources,” published February 27 in Nature Communications, a team led by Applied Physics Professor Alexander Gaeta has demonstrated a new approach to creating a source that can produce single photons of light on demand by combining photons at different colors and converting them into one color, a technique called frequency multiplexing. Generating single photons on demand is essential for future quantum technologies such as quantum computers and communications, which promise to revolutionize information processing.

A number of techniques have been established to generating precisely a single photon. However, in all cases the photons are produced in a probabilistic manner such that it is not known precisely when the single photon will be generated. An approach to making photon generation deterministic is to combine many of these probabilistic sources so that a single photon will be produced on demand. This combining of sources is known as multiplexing and has been demonstrated both in space and in time domains. However, as the number of sources is scaled up to make the generation process nearly deterministic, losses in the system can lead to diminishing returns and unacceptable performance.

“Our work breaks this key limitation since frequency multiplexing is inherently more tolerant of losses as compared to spatial or temporal multiplexing,” says Gaeta. “Our experiments establish this superior scaling by exploiting low-loss fiber optics technology. Moreover, our technique is ideally suited for chip-based integration, which offers the precision and repeatability essential for creating thousands of identical single-photon sources on a miniaturized platform.”

The authors are Chaitali Joshi (Columbia Engineering and Cornell University); Alessandro Farsi and Alexander L. Gaeta (Columbia Engineering);Stéphane Clemmen (Université Libre de Bruxelles); and Sven Ramelow (Humboldt-Universität zu Berlin). This work was funded by the National Science Foundation under Grants PHY-1404300 and EFMA-1641094. (March 1, 2018)

Originally published by Columbia Engineering

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