arXiv:quant-ph/0409162 · Physical Review A

Efficient and spectrally bright source of polarization-entangled photons

Friedrich König, Elliott J. Mason, Franco N. C. Wong, Marius A. Albotǎ

Published Mar 9, 2005• 70 citations

Abstract

We demonstrate an efficient fiber-coupled source of nondegenerate polarization-entangled photons at 795 and $1609\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ using bidirectionally pumped parametric down-conversion in bulk periodically poled lithium niobate. The single-mode source has an inferred bandwidth of $50\phantom{\rule{0.3em}{0ex}}\mathrm{GHz}$ and a spectral brightness of $300\phantom{\rule{0.3em}{0ex}}\text{pairs}∕(\mathrm{s}\phantom{\rule{0.2em}{0ex}}\mathrm{GHz}\phantom{\rule{0.2em}{0ex}}\mathrm{mW})$ of pump power that is suitable for narrowband applications such as entanglement transfer from photonic to atomic qubits.

DOI: 10.1103/physreva.71.033805

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arXiv:quant-ph/0409162 · Physical Review A

Efficient and spectrally bright source of polarization-entangled photons

Friedrich König, Elliott J. Mason, Franco N. C. Wong, Marius A. Albotǎ

Published Mar 9, 2005• 70 citations

arXiv HTML PDF

Abstract

We demonstrate an efficient fiber-coupled source of nondegenerate polarization-entangled photons at 795 and

1609\phantom{\rule{0.3em}{0ex}}\mathrm{nm}

using bidirectionally pumped parametric down-conversion in bulk periodically poled lithium niobate. The single-mode source has an inferred bandwidth of

50\phantom{\rule{0.3em}{0ex}}\mathrm{GHz}

and a spectral brightness of

300\phantom{\rule{0.3em}{0ex}}\text{pairs}∕(\mathrm{s}\phantom{\rule{0.2em}{0ex}}\mathrm{GHz}\phantom{\rule{0.2em}{0ex}}\mathrm{mW})

of pump power that is suitable for narrowband applications such as entanglement transfer from photonic to atomic qubits.

DOI: 10.1103/physreva.71.033805

Related papers

A high-flux source of single-mode fiber-coupled nondegenerate polarization-entangled photons

Franco N. C. Wong, Dheera Venkatraman

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIESep 9, 20070 citations

Generation of polarization-entangled photons using type-II doubly periodically poled lithium niobate waveguides

Krishna Thyagarajan, Jasleen Lugani, Sankalpa Ghosh +5 more

In this paper, we address the issue of the generation of nondegenerate cross-polarization-entangled photon pairs using type-II periodically poled lithium niobate. We show that, by an appropriate engineering of the quasi-phase-matching grating, it is possible to simultaneously satisfy the conditions for two spontaneous parametric down-conversion processes, namely, ordinary pump photon down conversion to either extraordinary signal and ordinary idler paired photons or to ordinary signal and extraordinary idler paired photons. In contrast to single type-II phase matching, these two processes, when enabled together, can lead to the direct production of cross-polarization-entangled states for nondegenerate signal and idler wavelengths. Such a scheme should be of great interest in applications requiring polarization-entangled nondegenerate paired photons with, for instance, one of the entangled photons at an appropriate wavelength being used for local operation or for quantum storage in an atomic ensemble and the other one at the typical wavelength of 1550 nm for propagation through an optical fiber.In this paper, we address the issue of the generation of nondegenerate cross-polarization-entangled photon pairs using type-II periodically poled lithium niobate. We show that, by an appropriate engineering of the quasi-phase-matching grating, it is possible to simultaneously satisfy the conditions for two spontaneous parametric down-conversion processes, namely, ordinary pump photon down conversion to either extraordinary signal and ordinary idler paired photons or to ordinary signal and extraordinary idler paired photons. In contrast to single type-II phase matching, these two processes, when enabled together, can lead to the direct production of cross-polarization-entangled states for nondegenerate signal and idler wavelengths. Such a scheme should be of great interest in applications requiring polarization-entangled nondegenerate paired photons with, for instance, one of the entangled photons at an appropriate wavelength being used for local operation or for quantum storage in an atomic ensemble and the other one at the typical wavelength of 1550 nm for propagation through an optical fiber.

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arXiv:1112.4551Physical Review ANov 14, 201147 citations

We demonstrate an efficient fiber-coupled source of nondegenerate polarization-entangled photons at 795 and

1609\phantom{\rule{0.3em}{0ex}}\mathrm{nm}

using bidirectionally pumped parametric down-conversion in bulk periodically poled lithium niobate. The single-mode source has an inferred bandwidth of

50\phantom{\rule{0.3em}{0ex}}\mathrm{GHz}

and a spectral brightness of

300\phantom{\rule{0.3em}{0ex}}\text{pairs}∕(\mathrm{s}\phantom{\rule{0.2em}{0ex}}\mathrm{GHz}\phantom{\rule{0.2em}{0ex}}\mathrm{mW})

of pump power that is suitable for narrowband applications such as entanglement transfer from photonic to atomic qubits.

3.6

GHz, and the spectral brightnesses are more than 100 pairs

/

(s GHz mW). Two concurrent quasi-phase-matched spontaneous parametric down-conversion processes in a single crystal enable our source to be compact and stable. This scheme does not rely on any state projection and applies to both degenerate and nondegenerate cases, facilitating applications of the entangled photons.