Quantum frequency conversion (QFC) of photonic signals preserves quantum information while simultaneously changing the signal wavelength. A common application of QFC is to translate the wavelength of a signal compatible with the current fiber-optic infrastructure to a shorter wavelength more compatible with high quality single-photon detectors and optical memories. Recent work has investigated the use of QFC to manipulate and measure specific temporal modes (TMs) through tailoring of the pump pulses. Such a scheme holds promise for multidimensional quantum state manipulation that is both low loss and re-programmable on a fast time scale. We demonstrate the first QFC temporal mode sorting system in a four-dimensional Hilbert space, achieving a conversion efficiency and mode separability as high as 92% and 0.84, respectively. A 20-GHz pulse train is projected onto 6 different TMs, including superposition states, and mode separability with weak coherent signals is verified via photon counting. Such ultrafast high-dimensional photonic signals could enable long-distance quantum communication with high rates.
@article{arxiv.1606.07794,
title = {Multidimensional mode-separable frequency conversion for high-speed quantum communication},
author = {Paritosh Manurkar and Nitin Jain and Michael Silver and Yu-Ping Huang and Carsten Langrock and Martin M. Fejer and Prem Kumar and Gregory S. Kanter},
journal= {arXiv preprint arXiv:1606.07794},
year = {2016}
}
Comments
Research article updated with reviewers' comments, journal reference and DOI