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:2112.06084 · Journal of the Optical Society of America B

Generation of nonclassical states of light via truncation of mixed states

E. P. Mattos, A. Vidiella-Barranco

Published Jun 8, 2022• 7 citations
arXivHTMLPDF

Abstract

A possible way of generating nonclassical states of light is via the truncation of a given state in the Fock basis. In recent work, we presented an alternative scheme for such quantum scissors [ Phys. Rev. A 104 , 033715 ( 2021 ) PLRAAN 1050-2947 10.1103/PhysRevA.104.033715 ], employing a nondegenerate parametric amplifier, a beam splitter, and photodetectors. An advantage of this setup is that it does not require the generation of Fock states beforehand, as in previous proposals. Here we extend this treatment to mixed input states. We show the possibilities of generating truncated states with either a maximum Fock number N or states having a minimum Fock number N . We discuss two specific examples of states to be truncated: (i) the thermal state and (ii) the phase-diffused coherent state. In either case, the generated field states can present sub-Poissonian statistics as well as non-Gaussian character. These nonclassical properties can be adjusted by changing the parameters of the scissors, e.g., the amplifier strength and the beam-splitter transmittance.

DOI
10.1364/josab.450622

Related papers

Quantum state truncation using an optical parametric amplifier and a beam splitter

E. P. Mattos, A. Vidiella-Barranco

We present a scheme of quantum state truncation in the Fock basis (quantum scissors), based on the combined action of a nondegenerate optical parametric amplifier and a beam splitter. Differently from previously proposed linear-optics-based quantum scissors devices, which depend on reliable Fock state sources, our scheme requires only readily available Gaussian states, such as coherent state inputs (vacuum state included). A truncated state is generated after performing photodetections in the global state. We find that, depending on which output ports each of the two photodetectors is positioned, different types of truncated states may be produced: (i) states having a maximum Fock number of $N$, or (ii) states having a minimum Fock number $N$. In order to illustrate our method, we discuss an example having as input states a coherent state in the beam splitter and vacuum states in the amplifier, and show that the resulting truncated states display nonclassical properties, such as sub-Poissonian statistics and squeezing. We quantify the nonclassicality degree of the generated states using the Wigner-Yanase skew information measure. For complementarity, we discuss the efficiency of the protocol, e.g., generation probability as well as the effects of imperfections such as the detector's quantum efficiency and dark counts rate.

arXiv:2109.12016•Physical Review A•Sep 24, 2021•12 citations

Enhancing nonclassical properties of quantum states of light using linear optics

E. P. Mattos, A. Vidiella-Barranco

In this Letter, we present a simple and versatile scheme for enhancing the nonclassical properties of light states using only linear optics and photodetectors. By combining a coherent state |α〉 and an arbitrary pure state of light |ϕ〉 (excluding coherent states) at two beam splitters, we show that the amplitude α of the coherent state can be tuned to filter out specific Fock components and generate states of light with increased nonclassical features. We provide two examples of input states and demonstrate the effectiveness of our scheme in enhancing the sub-Poissonian statistics or the quadrature squeezing of the output states.

arXiv:2310.04913•Optics Letters•Jun 15, 2023•2 citations

Fock-state filtering of squeezed states: enhanced nonclassicality and effects of a thermal bath

João Pedro Gonzalez de Oliveira, A. Vidiella-Barranco

The ability to tailor photon-number statistics is central to the generation and control of nonclassical states of light. Here, we investigate how Fock-state filtering of squeezed coherent states can be used to engineer their photon statistics. We consider the selective removal of the $m=0$ and $m=1$ Fock components and show that this process can enhance the sub-Poissonian character of the field, depending on the coherent amplitude. We then analyze the evolution of these engineered states in a thermal environment. Although all states eventually relax toward thermal statistics, the signatures of the filtering process may persist over a significant part of the evolution, while the purity of the filtered states is rapidly degraded by incoherent population redistribution. Our results illustrate both the potential and the limitations of photon-number engineering in realistic, dissipative settings.

quant-pharXiv:2608.22668•Brazilian Journal of Physics•Aug 25, 2026•0 citations

Nonclassical mixed states that generate zero entanglement with a beam splitter

Aaron Z. Goldberg, Daniel F. V. James

Abstract Beam splitters are routinely used for generating entanglement. Their entangling properties have been studied extensively, with nonclassicality of the input states a prerequisite for entanglement at the output. Here we quantify the amount of entanglement generated by weakly-reflecting beam splitters, and look for nonclassical states that are not entangled by general beam splitters. We extend the known class of results to mixed and non-Gaussian states, finding that inputting highly nonclassical combinations of unpolarized states that are squeezed and displaced onto a beam splitter can still yield separable output states. This is important in light of the challenge of characterizing mixed state entanglement. We further identify a parallel between SU(2) unpolarized states and the two-mode vacuum. Our result is crucial for understanding the generation of modal entanglement by beam splitters.

arXiv:1712.05425•Journal of Physics A Mathematical and Theoretical•Aug 3, 2018•8 citations

Generalized quantum scissors for noiseless linear amplification

Matthew S. Winnel, Nedasadat Hosseinidehaj, Timothy C. Ralph

We generalize the concept of optical state truncation and noiseless linear amplification to enable truncation of the Fock-state expansion of an optical state to higher order and to simultaneously amplify it using linear optics. The resulting generalized quantum scissors are more efficient for noiseless linear amplification than employing multiple scissors in parallel and are experimentally practical. As a particular example, we focus on a third-order scissor device and demonstrate advantages in terms of fidelity with the target state, probability of success, distillable entanglement, and the amount of non-Gaussianity introduced.

arXiv:2002.12566•Physical Review A•Dec 21, 2020•52 citations

Preparation and non-classicality of non-Gaussian quantum states based on catalytic quantum scissors

Kuizheng Zhang, Liyun Hu, Wei Ye +2 more

Abstract Based on the quantum scissor device proposed by Pegg et al , this paper implements a non-Gaussian quantum state preparation scheme. When considering the quantum photocatalysis of single-photon input and single-photon detection, the equivalent operator of catalytic quantum scissors is given in order to understand the physical nature of quantum scissors. When the coherent state is taken as the input state, for an asymmetric beam splitter, the output state can be truncated to zero photon, single photon and two photon components; for a symmetric beam splitter, the output state is only truncated to zero photon and two photon components. The non-classicality of the prepared non-Gaussian quantum states is discussed by the average photon number, signal-to-noise ratio, squeezing effcet and Wigner function. These results show that the output states can present strong non-classicality when modulating the amplitude of the coherent state and transmissivity of beam splitter.

Laser Physics Letters•Dec 6, 2018•16 citations
A possible way of generating nonclassical states of light is via the truncation of a given state in the Fock basis. In recent work, we presented an alternative scheme for such quantum scissors [ Phys. Rev. A 104 , 033715 ( 2021 ) PLRAAN 1050-2947 10.1103/PhysRevA.104.033715 ], employing a nondegenerate parametric amplifier, a beam splitter, and photodetectors. An advantage of this setup is that it does not require the generation of Fock states beforehand, as in previous proposals. Here we extend this treatment to mixed input states. We show the possibilities of generating truncated states with either a maximum Fock number N or states having a minimum Fock number N . We discuss two specific examples of states to be truncated: (i) the thermal state and (ii) the phase-diffused coherent state. In either case, the generated field states can present sub-Poissonian statistics as well as non-Gaussian character. These nonclassical properties can be adjusted by changing the parameters of the scissors, e.g., the amplifier strength and the beam-splitter transmittance.
We present a scheme of quantum state truncation in the Fock basis (quantum scissors), based on the combined action of a nondegenerate optical parametric amplifier and a beam splitter. Differently from previously proposed linear-optics-based quantum scissors devices, which depend on reliable Fock state sources, our scheme requires only readily available Gaussian states, such as coherent state inputs (vacuum state included). A truncated state is generated after performing photodetections in the global state. We find that, depending on which output ports each of the two photodetectors is positioned, different types of truncated states may be produced: (i) states having a maximum Fock number of NNN, or (ii) states having a minimum Fock number NNN. In order to illustrate our method, we discuss an example having as input states a coherent state in the beam splitter and vacuum states in the amplifier, and show that the resulting truncated states display nonclassical properties, such as sub-Poissonian statistics and squeezing. We quantify the nonclassicality degree of the generated states using the Wigner-Yanase skew information measure. For complementarity, we discuss the efficiency of the protocol, e.g., generation probability as well as the effects of imperfections such as the detector's quantum efficiency and dark counts rate.
In this Letter, we present a simple and versatile scheme for enhancing the nonclassical properties of light states using only linear optics and photodetectors. By combining a coherent state |α〉 and an arbitrary pure state of light |ϕ〉 (excluding coherent states) at two beam splitters, we show that the amplitude α of the coherent state can be tuned to filter out specific Fock components and generate states of light with increased nonclassical features. We provide two examples of input states and demonstrate the effectiveness of our scheme in enhancing the sub-Poissonian statistics or the quadrature squeezing of the output states.
The ability to tailor photon-number statistics is central to the generation and control of nonclassical states of light. Here, we investigate how Fock-state filtering of squeezed coherent states can be used to engineer their photon statistics. We consider the selective removal of the m=0m=0m=0 and m=1m=1m=1 Fock components and show that this process can enhance the sub-Poissonian character of the field, depending on the coherent amplitude. We then analyze the evolution of these engineered states in a thermal environment. Although all states eventually relax toward thermal statistics, the signatures of the filtering process may persist over a significant part of the evolution, while the purity of the filtered states is rapidly degraded by incoherent population redistribution. Our results illustrate both the potential and the limitations of photon-number engineering in realistic, dissipative settings.
Abstract Beam splitters are routinely used for generating entanglement. Their entangling properties have been studied extensively, with nonclassicality of the input states a prerequisite for entanglement at the output. Here we quantify the amount of entanglement generated by weakly-reflecting beam splitters, and look for nonclassical states that are not entangled by general beam splitters. We extend the known class of results to mixed and non-Gaussian states, finding that inputting highly nonclassical combinations of unpolarized states that are squeezed and displaced onto a beam splitter can still yield separable output states. This is important in light of the challenge of characterizing mixed state entanglement. We further identify a parallel between SU(2) unpolarized states and the two-mode vacuum. Our result is crucial for understanding the generation of modal entanglement by beam splitters.
We generalize the concept of optical state truncation and noiseless linear amplification to enable truncation of the Fock-state expansion of an optical state to higher order and to simultaneously amplify it using linear optics. The resulting generalized quantum scissors are more efficient for noiseless linear amplification than employing multiple scissors in parallel and are experimentally practical. As a particular example, we focus on a third-order scissor device and demonstrate advantages in terms of fidelity with the target state, probability of success, distillable entanglement, and the amount of non-Gaussianity introduced.
Abstract Based on the quantum scissor device proposed by Pegg et al , this paper implements a non-Gaussian quantum state preparation scheme. When considering the quantum photocatalysis of single-photon input and single-photon detection, the equivalent operator of catalytic quantum scissors is given in order to understand the physical nature of quantum scissors. When the coherent state is taken as the input state, for an asymmetric beam splitter, the output state can be truncated to zero photon, single photon and two photon components; for a symmetric beam splitter, the output state is only truncated to zero photon and two photon components. The non-classicality of the prepared non-Gaussian quantum states is discussed by the average photon number, signal-to-noise ratio, squeezing effcet and Wigner function. These results show that the output states can present strong non-classicality when modulating the amplitude of the coherent state and transmissivity of beam splitter.