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

arXiv:quant-ph/0304005 · Physical Review A

Conditional generation of arbitrary multimode entangled states of light with linear optics

Jaromı́r Fiurášek, Serge Massar, Nicolas J. Cerf

Published Oct 23, 2003• 21 citations
arXivHTMLPDF

Abstract

We propose a universal scheme for the probabilistic generation of an arbitrary multimode entangled state of light with finite expansion in Fock basis. The suggested setup involves passive linear optics, single-photon sources, strong coherent laser beams, and photodetectors with single-photon resolution. The efficiency of this setup may be greatly enhanced if, in addition, a quantum memory is available.

DOI
10.1103/physreva.68.042325

Related papers

Conditional generation of arbitrary single-mode quantum states of light by repeated photon subtractions

Jaromı́r Fiurášek, Raúl García−Patrón, Nicolas J. Cerf

We propose a scheme for the conditional generation of arbitrary finite superpositions of Fock states in a single mode of a traveling optical field. The setup requires a source of squeezed vacuum states, beam splitters, strong coherent beams, photodetectors with single-photon sensitivity, and a final squeezer. If we want to generate a squeezed superposition of Fock states, which is sufficient in several applications, then the last squeezer is not even needed. The thrust of this method is that it achieves a high fidelity without requiring photodetectors with a high efficiency or a single-photon resolution. The possibility to improve its scaling by using a quantum memory is also discussed.

arXiv:quant-ph/0503111•Physical Review A•Sep 23, 2005•123 citations

Conditional generation ofN-photon entangled states of light

Jaromı́r Fiurášek

We propose a scheme for conditional generation of two-mode N-photon path-entangled states of traveling light field. These states may find applications in quantum optical lithography and they may be used to improve the sensitivity of interferometric measurements. Our method requires only single-photon sources, linear optics (beam splitters and phase shifters), and photodetectors with single-photon sensitivity.

arXiv:quant-ph/0110138•Physical Review A•May 8, 2002•147 citations

Generation of Large Photon-Number Cat States using Linear Optics and Quantum Memory

Nicolas J. Cerf, Jaromı́r Fiurášek, S. Iblisdir +1 more

A recursive method for producing path-entangled states of light is presented. These states may find applications in quantum lithography and high-precision interferometric measurements. The required resources are single-photon sources, linear optics components, and photodetectors. Adding a quantum memory greatly enhances the yield in comparison with the previously known schemes.

arXiv:quant-ph/0210059•Oct 9, 2002•0 citations

Generation of arbitrary symmetric entangled states with conditional linear optical coupling

A. V. Sharypov, Bing He

An approach to generating the entangled photonic states $|{\ensuremath{\Psi}}_{1},{\ensuremath{\Psi}}_{2}\ensuremath{\rangle}\ifmmode\pm\else\textpm\fi{}|{\ensuremath{\Psi}}_{2},{\ensuremath{\Psi}}_{1}\ensuremath{\rangle}$ from two arbitrary states $|{\ensuremath{\Psi}}_{1}\ensuremath{\rangle}$ and $|{\ensuremath{\Psi}}_{2}\ensuremath{\rangle}$ is proposed. The protocol is implemented by the conditionally induced beam-splitter coupling, which leads to the selective swapping between two photonic modes. Such coupling occurs in a quantum system prepared in the superposition of two ground states with only one of them being involved in the swapping. All the entangled states in the category, such as entangled pairs of coherent states or Fock states (NOON states), can be efficiently produced in the same way by this method.

arXiv:1211.3330•Physical Review A•Mar 19, 2013•10 citations

Realization of multimode operators with passive linear optics and photodetection

J. Clausen, L. Knöll, D.‐G. Welsch

A scheme is proposed for implementing a desired transformation of the unknown quantum state of a traveling optical multimode signal. The operator describing this transformation is built up as a polynomial in products of the mode operators. There is no limitation to unitary operators realized by the scheme, the implementation is conditional however, i.e., the desired operator can be realized only with a certain success probability which depends on the respective operator and the input state. While the scheme requires the preparation of single-photon and coherent states, it exclusively makes use of beam splitters and zero- and single-photon detections. The setup consists of a number of stations, each controlling one of the signal modes. The stations share an auxiliary entangled state which has been prepared beforehand. This state is then entangled with each of the signal modes and a measurement is performed of each of the auxiliary modes afterwards. In this way, the stations can be spatially separated from one another, similar to a multimode generalization of a quantum teleportation setup. Some examples of application such as the realization of cross-Kerr nonlinearities, multidirectional quantum teleportation (i.e., multimode mirrors), and the preparation of multimode Greenberger-Horne-Zeilinger- and Einstein-Podolsky-Rosen-like states are considered.

arXiv:quant-ph/0303004•Physical Review A•Oct 22, 2003•10 citations

Deterministic Generation of Light-Matter Entangled States for Realization of Quantum Repeaters

Priyanshu Tiwari, Aleksa Krstić, Frank Setzpfandt +2 more

Quantum repeaters are vital ingredients for realization of long-distance quantum networks [1]. They can be realized by preparing nodes that can generate an entangled light-matter state, namely, a single photon entangled to a quantum memory. This allows for entangling two distant quantum memories, by propagating the single photons from each node to an intermediate place for Bell state measurements. A common approach for generating such entangled light-matter states is generating an entangled photon pair in a nonlinear source, and coupling one of the photons in the pair to a quantum memory for storage [2]. However, such an approach faces two main challenges: Photon-pair generation in nonlinear sources is a probabilistic process. Moreover, due to modal and spectral mismatches, coupling single photons from a nonlinear source to a quantum memory is generally not an efficient process. These make the successful generation of an entangled light-matter state highly probabilistic.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 23, 2025•0 citations
We propose a universal scheme for the probabilistic generation of an arbitrary multimode entangled state of light with finite expansion in Fock basis. The suggested setup involves passive linear optics, single-photon sources, strong coherent laser beams, and photodetectors with single-photon resolution. The efficiency of this setup may be greatly enhanced if, in addition, a quantum memory is available.
We propose a scheme for the conditional generation of arbitrary finite superpositions of Fock states in a single mode of a traveling optical field. The setup requires a source of squeezed vacuum states, beam splitters, strong coherent beams, photodetectors with single-photon sensitivity, and a final squeezer. If we want to generate a squeezed superposition of Fock states, which is sufficient in several applications, then the last squeezer is not even needed. The thrust of this method is that it achieves a high fidelity without requiring photodetectors with a high efficiency or a single-photon resolution. The possibility to improve its scaling by using a quantum memory is also discussed.
An approach to generating the entangled photonic states $|{\ensuremath{\Psi}}_{1},{\ensuremath{\Psi}}_{2}\ensuremath{\rangle}\ifmmode\pm\else\textpm\fi{}|{\ensuremath{\Psi}}_{2},{\ensuremath{\Psi}}_{1}\ensuremath{\rangle}$ from two arbitrary states $|{\ensuremath{\Psi}}_{1}\ensuremath{\rangle}$ and $|{\ensuremath{\Psi}}_{2}\ensuremath{\rangle}$ is proposed. The protocol is implemented by the conditionally induced beam-splitter coupling, which leads to the selective swapping between two photonic modes. Such coupling occurs in a quantum system prepared in the superposition of two ground states with only one of them being involved in the swapping. All the entangled states in the category, such as entangled pairs of coherent states or Fock states (NOON states), can be efficiently produced in the same way by this method.
A scheme is proposed for implementing a desired transformation of the unknown quantum state of a traveling optical multimode signal. The operator describing this transformation is built up as a polynomial in products of the mode operators. There is no limitation to unitary operators realized by the scheme, the implementation is conditional however, i.e., the desired operator can be realized only with a certain success probability which depends on the respective operator and the input state. While the scheme requires the preparation of single-photon and coherent states, it exclusively makes use of beam splitters and zero- and single-photon detections. The setup consists of a number of stations, each controlling one of the signal modes. The stations share an auxiliary entangled state which has been prepared beforehand. This state is then entangled with each of the signal modes and a measurement is performed of each of the auxiliary modes afterwards. In this way, the stations can be spatially separated from one another, similar to a multimode generalization of a quantum teleportation setup. Some examples of application such as the realization of cross-Kerr nonlinearities, multidirectional quantum teleportation (i.e., multimode mirrors), and the preparation of multimode Greenberger-Horne-Zeilinger- and Einstein-Podolsky-Rosen-like states are considered.
Quantum repeaters are vital ingredients for realization of long-distance quantum networks [1]. They can be realized by preparing nodes that can generate an entangled light-matter state, namely, a single photon entangled to a quantum memory. This allows for entangling two distant quantum memories, by propagating the single photons from each node to an intermediate place for Bell state measurements. A common approach for generating such entangled light-matter states is generating an entangled photon pair in a nonlinear source, and coupling one of the photons in the pair to a quantum memory for storage [2]. However, such an approach faces two main challenges: Photon-pair generation in nonlinear sources is a probabilistic process. Moreover, due to modal and spectral mismatches, coupling single photons from a nonlinear source to a quantum memory is generally not an efficient process. These make the successful generation of an entangled light-matter state highly probabilistic.