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

Acta Sinica Quantum Optica

Entanglement Change of Two-mode Squeezed Thermal State before and after a Beam Splitter

Hu Pen

Published Jan 1, 2014• 0 citations
OpenAlex

Abstract

In this paper,we adopted logarithmic negativity to evaluate the entanglement properties of twomode squeezed thermal state(TMSTS)before and after the beam splitter.It was found that when the input was symmetrical TMSTS,no matter how to adjust the relevant parameters of the beam splitter,entanglement did not change;for asymmetric TMSTS,entanglement may change in the appropriate range of the parameter of the beam splitter.

Related papers

Entanglement and Statistical Properties of Squeezed Vacuum State after an Beam Splitter

Hu Pen

Based on phase space method,we study entanglement and statistical properties of squeezed vacuum state after an beam splitter.We adopt the criterion of logarithmic negativity to study the entanglement properties of the output light field.The results show that the maximum entanglement is found for the symmetrical beam splitter and the amount of entanglement increases with the squeezing parameter.In addition,we also use the Wigner-Weyl rules to study the statistical properties of light field in one of the output ports.It is found that the nonclassicality of the output field will change by adjusting the relative parameter of the input light field and the beam splitter.

Journal of Jiangxi Normal University•Jan 1, 2013•0 citations

Entanglement and nonclassicality of photon-added two-mode squeezed thermal state

Liyun Hu, Fang Jia, Zhi‐Ming Zhang

We introduce a kind of entangled state—a photon-addition two-mode squeezed thermal state (TMSTS)—by adding photons to each mode of the TMSTS. Using the P-representation of thermal state, the compact expression of the normalization factor is derived, a Jacobi polynomial. The nonclassicality is investigated by exploring especially the negativity of Wigner function. The entanglement is discussed by using Shchukin–Vogel criteria. It is shown that the photon addition to the TMSTS may be more effective for the entanglement enhancement than the photon subtraction from the TMSTS. In addition, the quantum teleportation is also examined, which shows that symmetrical photon-added TMSTS may be more useful for quantum teleportation than the nonsymmetric case.

arXiv:1203.0595•Journal of the Optical Society of America B•May 30, 2012•54 citations

Entanglement and disentanglement from cascade beam-splitter for squeezed vacuum state inputs

Qingping Zhou, Mao-Fa Fang, Xiaojuan Liu +3 more

Properties of the entanglement at the outputs of a cascade beam-splitter are investigated for two single-mode squeezed vacuum state inputs. It is shown that the entanglement depends on the squeezing amplitudes of the input states and the reflection coefficients of the cascade beam-splitter and the composite phase shift Δ between the cascade beam-splitter and the input fields has a great effect on the entanglement. In particular, the properties of the entanglement of a cascade beam-splitter differ from those of only one beam-splitter. A further method for manipulating entanglement by adjusting the parameters of the cascade beam-splitter and the input fields is proposed.

Chinese Physics•Oct 26, 2004•10 citations

Entanglement of Gaussian states using a beam splitter

Rabia Tahira, Manzoor Ikram, Hyunchul Nha +1 more

We study an experimental scheme to generate Gaussian two-mode entangled states via beam splitter. Specifically, we consider a nonclassical Gaussian state (squeezed state) and a thermal state as two input modes, and evaluate the degree of entanglement at the output. Experimental conditions to generate entangled outputs are completely identified and the critical thermal noise to destroy entanglement is analytically obtained. By doing so, we discuss the possibility to link the resistance to noise in entanglement generation with the degree of single-mode nonclassicality.

arXiv:0810.1399•Physical Review A•Feb 12, 2009•57 citations

Conservation relation of nonclassicality and entanglement for Gaussian states in a beam splitter

Wenchao Ge, Mehmet Emre Taşgın, Muhammad Suhail Zubairy

We study the relation between single-mode nonclassicality and two-mode entanglement in a beam splitter. We show that single-mode nonclassicality (the entanglement potential) of incident light cannot be transformed into two-mode entanglement completely after a single beam splitter. Some of the entanglement potential remains as single-mode nonclassicality in the two entangled output modes. Two-mode entanglement generated in the process can be equivalently quantified as an increase in the minimum uncertainty widths (or decrease in the squeezing) of the output states compared to the input states. We use the nonclassical depth and logarithmic negativity as single-mode nonclassicality and entanglement measures, respectively. We realize that a conservation relation between the two quantities can be adopted for Gaussian states, if one works in terms of uncertainty width. This conservation relation is extended to many sets of beam splitters.

arXiv:1506.04937•Physical Review A•Nov 20, 2015•64 citations

Entanglement of one- and two-mode combination squeezed thermal states and its application in quantum teleportation

Liu Shi-You, Zheng Kai-Min, Fang Jia +2 more

In view of the fact that one- and two-mode combination squeezed vacuum states may exhibit stronger squeezing in a certain range, we introduce one- and two-mode combination squeezed thermal states (OTCSTS) and investigate the property of entanglement in detail. Using the remarkable property of Weyl ordering, i.e., the order-invariance of Weyl ordered operator under similar transformations, we conveniently derive the analytical expression of entanglement degree-logarithmic negativity, and then present the condition of keeping entanglement for these squeezed thermal states. It is found that the OTCSTS possesses higher entanglement than the usual two-mode squeezed thermal states for any non-zero squeezing parameter. As an application, the quantum teleportation for coherent state is considered by using the OTCSTS as an entangled channel. It is shown that the teleportation fidelity can only be enhanced within a certain range of parameters, which is just the same as the condition of exhibiting stronger squeezing in one quadrature. In addition, the condition of realizing effective quantum teleportation (>1/2) is obtained analytically.

Acta Physica Sinica•Jan 1, 2014•2 citations
In this paper,we adopted logarithmic negativity to evaluate the entanglement properties of twomode squeezed thermal state(TMSTS)before and after the beam splitter.It was found that when the input was symmetrical TMSTS,no matter how to adjust the relevant parameters of the beam splitter,entanglement did not change;for asymmetric TMSTS,entanglement may change in the appropriate range of the parameter of the beam splitter.
Based on phase space method,we study entanglement and statistical properties of squeezed vacuum state after an beam splitter.We adopt the criterion of logarithmic negativity to study the entanglement properties of the output light field.The results show that the maximum entanglement is found for the symmetrical beam splitter and the amount of entanglement increases with the squeezing parameter.In addition,we also use the Wigner-Weyl rules to study the statistical properties of light field in one of the output ports.It is found that the nonclassicality of the output field will change by adjusting the relative parameter of the input light field and the beam splitter.
We introduce a kind of entangled state—a photon-addition two-mode squeezed thermal state (TMSTS)—by adding photons to each mode of the TMSTS. Using the P-representation of thermal state, the compact expression of the normalization factor is derived, a Jacobi polynomial. The nonclassicality is investigated by exploring especially the negativity of Wigner function. The entanglement is discussed by using Shchukin–Vogel criteria. It is shown that the photon addition to the TMSTS may be more effective for the entanglement enhancement than the photon subtraction from the TMSTS. In addition, the quantum teleportation is also examined, which shows that symmetrical photon-added TMSTS may be more useful for quantum teleportation than the nonsymmetric case.
Properties of the entanglement at the outputs of a cascade beam-splitter are investigated for two single-mode squeezed vacuum state inputs. It is shown that the entanglement depends on the squeezing amplitudes of the input states and the reflection coefficients of the cascade beam-splitter and the composite phase shift Δ between the cascade beam-splitter and the input fields has a great effect on the entanglement. In particular, the properties of the entanglement of a cascade beam-splitter differ from those of only one beam-splitter. A further method for manipulating entanglement by adjusting the parameters of the cascade beam-splitter and the input fields is proposed.
We study an experimental scheme to generate Gaussian two-mode entangled states via beam splitter. Specifically, we consider a nonclassical Gaussian state (squeezed state) and a thermal state as two input modes, and evaluate the degree of entanglement at the output. Experimental conditions to generate entangled outputs are completely identified and the critical thermal noise to destroy entanglement is analytically obtained. By doing so, we discuss the possibility to link the resistance to noise in entanglement generation with the degree of single-mode nonclassicality.
We study the relation between single-mode nonclassicality and two-mode entanglement in a beam splitter. We show that single-mode nonclassicality (the entanglement potential) of incident light cannot be transformed into two-mode entanglement completely after a single beam splitter. Some of the entanglement potential remains as single-mode nonclassicality in the two entangled output modes. Two-mode entanglement generated in the process can be equivalently quantified as an increase in the minimum uncertainty widths (or decrease in the squeezing) of the output states compared to the input states. We use the nonclassical depth and logarithmic negativity as single-mode nonclassicality and entanglement measures, respectively. We realize that a conservation relation between the two quantities can be adopted for Gaussian states, if one works in terms of uncertainty width. This conservation relation is extended to many sets of beam splitters.
In view of the fact that one- and two-mode combination squeezed vacuum states may exhibit stronger squeezing in a certain range, we introduce one- and two-mode combination squeezed thermal states (OTCSTS) and investigate the property of entanglement in detail. Using the remarkable property of Weyl ordering, i.e., the order-invariance of Weyl ordered operator under similar transformations, we conveniently derive the analytical expression of entanglement degree-logarithmic negativity, and then present the condition of keeping entanglement for these squeezed thermal states. It is found that the OTCSTS possesses higher entanglement than the usual two-mode squeezed thermal states for any non-zero squeezing parameter. As an application, the quantum teleportation for coherent state is considered by using the OTCSTS as an entangled channel. It is shown that the teleportation fidelity can only be enhanced within a certain range of parameters, which is just the same as the condition of exhibiting stronger squeezing in one quadrature. In addition, the condition of realizing effective quantum teleportation (>1/2) is obtained analytically.