Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Theory of spontaneous parametric down-conversion from photonic crystals

A. Nick Vamivakas, Bahaa E. A. Saleh, Alexander V. Sergienko, Malvin Carl Teich

Published Oct 14, 2004• 36 citations
Publisher

Abstract

An effective-medium approach is used to derive a set of coupled-mode equations describing quadratic parametric interactions in a one-dimensional inhomogeneous medium of finite length. The solutions for both copropagating and counterpropagating interactions are used to study the quantum-mechanical process of spontaneous parametric down-conversion (SPDC). An example is studied in which the inhomogeneous medium is a photonic crystal. The effect that device geometry has on both the efficiency and bandwidth of SPDC is explored. With appropriate design, we find that it is possible not only to enhance the efficiency of SPDC, but also to generate broadband copropagating and narrowband counterpropagating down-converted light. A setup is proposed with the potential to act as a source of entangled photon pairs.

DOI
10.1103/physreva.70.043810

Related papers

Characterization of Broadband Spontaneous Parametric Down-Conversion in Periodically Poled Materials

Chiara Lindner, Sebastian Wolf, Jens Kießling +1 more

Spontaneous parametric down-conversion (SPDC) is one of the most important sources for entangled or correlated photon pairs, which are the foundation of the emerging fields of quantum-optical imaging and spectroscopy. Using periodically poled materials as an SPDC-source allows broad emission spectra in widely tunable wavelength ranges in an efficient and walk-off-free process. For applications that employ nonlinear interference setups, maximum interferometric contrast is only achieved when signal and idler modes are overlapped precisely in the second crystal. Thus, accurate knowledge of the spectral-angular characteristic of SPDC is crucial for designing such devices.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 1, 2019•0 citations

Entangled photon pair generation by spontaneous parametric down-conversion in finite-length one-dimensional photonic crystals

Marco Centini, Jan Peřina, Letizia Sciscione +4 more

A description of spontaneous parametric down-conversion in finite-length one-dimensional nonlinear photonic crystals is developed using semiclassical and quantum approaches. It is shown that if a suitable averaging is added to the semiclassical model, its results are in very good agreement with the quantum approach. We propose two structures made with $\mathrm{Ga}\mathrm{N}∕\mathrm{Al}\mathrm{N}$ that generate both degenerate and nondegenerate entangled photon pairs. Both structures are designed so as to achieve a high efficiency of the nonlinear process.

Physical Review A•Sep 9, 2005•31 citations

A source of polarization entangled photon pairs based on two-dimensional photonic crystals

Li Xiao, Yin Wang, Wei Zhang +2 more

Spontaneous parametric down-conversion in two-dimensional photonic crystal made of semiconductor material with large quadratic nonlinear susceptibility is proposed to generate polarization entangled photon pairs. On one hand, the large quadratic nonlinear susceptibility of AlGaAs crystal insures the high nonlinear conversion efficiency; on the other hand, the abnormal dispersion property of two-dimensional photonic crystal causes the satisfaction of the phase-matching condition. In particular, the dispersion property sensitively depends on the structure of photonic crystal. Then the walk-off between the down-converted photons with orthogonal polarizations can be minimized through appropriate structure parameter design; hence compensation measures to mitigate labeling effect on polarization entangled photon pairs can be eliminated.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 22, 2006•0 citations

Optimizing Spontaneous Parametric Down Conversion in Metasurfaces with Inverse Design

Marcus Cai, Neuton Li, Tongmiao Fan +4 more

Spontaneous parametric down conversion (SPDC) is one of the most versatile techniques for the generation of correlated photon pair, whose quantum state is essential for photon entanglement that underpins many quantum applications like secure communication, quantum metrology and lithography and quantum imaging [1]. Inverse design of effective SPDC has been achieved by structured crystals with shaped pump beams [2]. Another popular platform for SPDC is nanofabricated structures with sub-wavelength thickness called metasurfaces, as they could achieve drastic enhancement of nonlinear light-matter interactions [3]. There remains the possibility to use inverse design to optimize metasurfaces for SPDC.

JSAP-OSA Joint Symposia•Jan 1, 2024•0 citations

Background and Review of Cavity-Enhanced Spontaneous Parametric Down-Conversion

Oliver Slattery, Lijun Ma, Kevin Zong +1 more

Spontaneous parametric down-conversion (SPDC) in a nonlinear crystal has been a workhorse for the generation of entangled and correlated single-photon pairs used for quantum communications applications for nearly three decades. However, as a naturally broadband process, the ability of SPDC to interface with the very narrow energy transitions in atomic ensembles for implementing quantum memories, which are needed for quantum repeaters to extend the reach of quantum communications, was initially limited. To overcome this limitation, the process was enhanced by placing the nonlinear crystal inside a resonating cavity. This modified process has some important advantages, including narrowing the spectral linewidth of generated photons into brighter resonant modes of the cavity, and the ability to lock the desired mode of the cavity to the targeted transition frequency of the atomic ensemble. This paper presents an overview of the principle of cavity-enhanced SPDC, a review of works to date using this technique, and an example of one of these implementations.

Journal of Research of the National Institute of Standards and Technology•Aug 15, 2019•66 citations

Counterpropagating path-entangled photon pair sources based on simultaneous spontaneous parametric down-conversion processes of nonlinear photonic crystal

Can Yang, Chaoxiang Xi, Jietai Jing +1 more

Ultra-bright source of entangled photons is an essential component in optical quantum information processing. Here we propose a counterpropagating path-entangled photon pair sources using a quasi-periodic modulated lithium niobate crystal. The nonlinear crystal designed by a dual-grid method, simultaneously phase-matched two spontaneous parametric down-conversion processes. Signal and idler modes have opposite propagation directions in the two spontaneous parametric down-conversion processes, which is the key to generating path-entangled photon pairs. Compared to copropagating entangled sources, the counterpropagating path-entangled sources result in a much narrower spectrum. The quantum state of the path-entanglement source is not only suited for quantum coding, but also to allow the implementation of complex quantum algorithms on a photonic chip.

Optics Express•Oct 9, 2018•4 citations
An effective-medium approach is used to derive a set of coupled-mode equations describing quadratic parametric interactions in a one-dimensional inhomogeneous medium of finite length. The solutions for both copropagating and counterpropagating interactions are used to study the quantum-mechanical process of spontaneous parametric down-conversion (SPDC). An example is studied in which the inhomogeneous medium is a photonic crystal. The effect that device geometry has on both the efficiency and bandwidth of SPDC is explored. With appropriate design, we find that it is possible not only to enhance the efficiency of SPDC, but also to generate broadband copropagating and narrowband counterpropagating down-converted light. A setup is proposed with the potential to act as a source of entangled photon pairs.
Spontaneous parametric down-conversion (SPDC) is one of the most important sources for entangled or correlated photon pairs, which are the foundation of the emerging fields of quantum-optical imaging and spectroscopy. Using periodically poled materials as an SPDC-source allows broad emission spectra in widely tunable wavelength ranges in an efficient and walk-off-free process. For applications that employ nonlinear interference setups, maximum interferometric contrast is only achieved when signal and idler modes are overlapped precisely in the second crystal. Thus, accurate knowledge of the spectral-angular characteristic of SPDC is crucial for designing such devices.
A description of spontaneous parametric down-conversion in finite-length one-dimensional nonlinear photonic crystals is developed using semiclassical and quantum approaches. It is shown that if a suitable averaging is added to the semiclassical model, its results are in very good agreement with the quantum approach. We propose two structures made with GaN∕AlN\mathrm{Ga}\mathrm{N}∕\mathrm{Al}\mathrm{N}GaN∕AlN that generate both degenerate and nondegenerate entangled photon pairs. Both structures are designed so as to achieve a high efficiency of the nonlinear process.
Spontaneous parametric down-conversion in two-dimensional photonic crystal made of semiconductor material with large quadratic nonlinear susceptibility is proposed to generate polarization entangled photon pairs. On one hand, the large quadratic nonlinear susceptibility of AlGaAs crystal insures the high nonlinear conversion efficiency; on the other hand, the abnormal dispersion property of two-dimensional photonic crystal causes the satisfaction of the phase-matching condition. In particular, the dispersion property sensitively depends on the structure of photonic crystal. Then the walk-off between the down-converted photons with orthogonal polarizations can be minimized through appropriate structure parameter design; hence compensation measures to mitigate labeling effect on polarization entangled photon pairs can be eliminated.
Spontaneous parametric down conversion (SPDC) is one of the most versatile techniques for the generation of correlated photon pair, whose quantum state is essential for photon entanglement that underpins many quantum applications like secure communication, quantum metrology and lithography and quantum imaging [1]. Inverse design of effective SPDC has been achieved by structured crystals with shaped pump beams [2]. Another popular platform for SPDC is nanofabricated structures with sub-wavelength thickness called metasurfaces, as they could achieve drastic enhancement of nonlinear light-matter interactions [3]. There remains the possibility to use inverse design to optimize metasurfaces for SPDC.
Spontaneous parametric down-conversion (SPDC) in a nonlinear crystal has been a workhorse for the generation of entangled and correlated single-photon pairs used for quantum communications applications for nearly three decades. However, as a naturally broadband process, the ability of SPDC to interface with the very narrow energy transitions in atomic ensembles for implementing quantum memories, which are needed for quantum repeaters to extend the reach of quantum communications, was initially limited. To overcome this limitation, the process was enhanced by placing the nonlinear crystal inside a resonating cavity. This modified process has some important advantages, including narrowing the spectral linewidth of generated photons into brighter resonant modes of the cavity, and the ability to lock the desired mode of the cavity to the targeted transition frequency of the atomic ensemble. This paper presents an overview of the principle of cavity-enhanced SPDC, a review of works to date using this technique, and an example of one of these implementations.
Ultra-bright source of entangled photons is an essential component in optical quantum information processing. Here we propose a counterpropagating path-entangled photon pair sources using a quasi-periodic modulated lithium niobate crystal. The nonlinear crystal designed by a dual-grid method, simultaneously phase-matched two spontaneous parametric down-conversion processes. Signal and idler modes have opposite propagation directions in the two spontaneous parametric down-conversion processes, which is the key to generating path-entangled photon pairs. Compared to copropagating entangled sources, the counterpropagating path-entangled sources result in a much narrower spectrum. The quantum state of the path-entanglement source is not only suited for quantum coding, but also to allow the implementation of complex quantum algorithms on a photonic chip.