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PHOTON INDUCED ENTANGLEMENT IN ATOM-CAVITY SYSTEMS

LI-LI LAN, XIANG-BIN WANG, SHAO-MING FEI
2010 International Journal of Quantum Information  
We study the evolution of quantum entanglement in double cavity systems. The entanglement of cavity atoms induced by entangled pair of photons is investigated.  ...  We also propose a strategy to enhance the entanglement between the atom in one cavity and the photon in another cavity by using quantum Zeno effect.  ...  We use concurrence as the measure to characterize the quantum entanglement of a two-qubit state ρ [10] , C(ρ) = max{0, λ 1 − λ 2 − λ 3 − λ 4 }, where λ i are the eigenvalues, in decreasing order, of the  ... 
doi:10.1142/s0219749910006976 fatcat:77oiee6o6rhydaanolqeowfnxe

Photon polarization entanglement from distant dipole sources

Yuan Liang Lim, Almut Beige
2004 Journal of Physics A: Mathematical and General  
In the case of two sources, the entanglement arises under the condition of two emissions in certain spatial directions and leaves the dipoles in a maximally entangled state.  ...  In contrast to this, we show here that polarisation entanglement can also be produced by distant single photon sources in free space and without the photons ever having to meet, if the detection of a photon  ...  L. acknowledges funding from the DSO National Laboratories in Singapore. A. B. thanks the Royal Society and the GCHQ for funding as a James Ellis University Research Fellow.  ... 
doi:10.1088/0305-4470/38/1/l02 fatcat:j37ggau7tfdwroyuuipr7pk3qe

Heralded entanglement of arbitrary degree in remote qubits

U. Schilling, C. Thiel, E. Solano, T. Bastin, J. von Zanthier
2009 Physical Review A. Atomic, Molecular, and Optical Physics  
Incoherent scattering of photons off two remote atoms with a Lambda-level structure is used as a basic Young-type interferometer to herald long-lived entanglement of an arbitrary degree.  ...  An estimate of the variation in the degree of entanglement due to uncertainties in an experimental realization is given.  ...  [5] showed that the interference pattern of a single photon probing two spatially separated atomic systems can witness their mutual entanglement.  ... 
doi:10.1103/physreva.80.022312 fatcat:xalc2sue4zed3eopqb7zqaoqz4

Photon statistics on the extreme entanglement

Yang Zhang, Jun Zhang, Chang-shui Yu
2016 Scientific Reports  
Here we design a cavity quantum electrodynamics model with two atoms trapped in to demonstrate the connections between the steady-state photon statistics and the two-atom entanglement.  ...  It is found that within the weak dissipations and to some good approximation, the local maximal two-atom entanglements perfectly correspond to not only the quantum feature of the electromagnetic field-the  ...  Once such transitions happen, the trapped double atoms have 50% probability to only absorb one photon to form a maximally-entangled-state component in the corresponding eigen-mode.  ... 
doi:10.1038/srep24098 pmid:27053368 pmcid:PMC4823655 fatcat:t7jt7ug7tre2tht5amufgo6gea

Quantum computing and quantum communication with atoms

L.-M. Duan, W. Dür, J.I. Cirac, D. Jaksch, G. Vidal, P. Zoller
2003 The Expanding Frontier of Atomic Physics  
The first example deals with the realization of a universal quantum simulator with atoms and ions. The second example outlines the implementation of a quantum repeater with atomic ensembles.  ...  We review recent theoretical proposals for implementation of quantum computing and quantum communication with atoms.  ...  [4] atoms can be loaded in a double optical lattice, and cold controlled collisions provide a way of entangling these atoms.  ... 
doi:10.1142/9789812705099_0028 fatcat:kzty3rg4vvhhjgbzgkluzss5ti

Photon statistics on the extreme entanglement [article]

Yang Zhang, Jun Zhang, Chang-shui Yu
2016 arXiv   pre-print
Here we design a cavity quantum electrodynamics model with two atoms trapped in to demonstrate the connections between the steady-state photon statistics and the two-atom entanglement .  ...  It is found that within the weak dissipations and to some good approximation, the local maximal two-atom entanglements perfectly correspond to not only the quantum feature of the electromagnetic field-  ...  Once such transitions happen, the trapped double atoms have 50% probability to only absorb one photon to form a maximally-entangled-state component in the corresponding eigen-mode.  ... 
arXiv:1604.02203v1 fatcat:53fmhixqybcbfnufdyhv2rg2w4

Maximal atom-photon entanglement in an N-type atomic system [article]

Seyedeh Hamideh Kazemi, Nayyere Einali Saghavaz, Mohammad Mahmoudi
2018 arXiv   pre-print
Atom-photon entanglement provides an essential resource for quantum communication and quantum computation.  ...  Here, we present a simple, yet we believe a powerful, method to generate entangled states between photons and an N-type atomic system.  ...  In this study, we consider the interaction of an atom with three coherent laser fields and demonstrate an atom-photon entanglement in a four-level N-type quantum system.  ... 
arXiv:1805.05831v1 fatcat:2rokp2no2fey3pjizhwobe4jhi

Entanglement of individual photon and atomic ensembles [article]

Guo-Ping Guo, Guang-Can Guo
2003 arXiv   pre-print
Furthermore, the present scheme can be modified to generate this entanglement in a way event-ready with the employment of a pair of entangled photons.  ...  This entanglement integrate two different species can act as a critical element for the coherent transform of quantum information between flying and stationary qubits.  ...  In the case there is only one Stokes photon, the whole system of the two atomic ensembles and this photon can be written in state |Φ ap = (αS † 1 P a † R + βS † 2 a † R ) |0 a |0 p , (1) where 1 and 2  ... 
arXiv:quant-ph/0206041v3 fatcat:vsyzxyschvdofm6w7npofxxnee

Heralded quantum repeater based on the scattering of photons off single emitters using parametric down-conversion source

Guo-Zhu Song, Fang-Zhou Wu, Mei Zhang, Guo-Jian Yang
2016 Scientific Reports  
Λ -system and V-system if both transitions couple to the waveguides.  ...  In 2014, Wang et al. 18 proposed a scheme for a quantum repeater based on a quantum dot in an optical microcavity system.  ...  In fact, utilizing entanglement concentration 57-59 , one can distill a subset system in a maximally entangled state from less-entangled pure state systems, and using entanglement purification 60-74 ,  ... 
doi:10.1038/srep28744 pmid:27350159 pmcid:PMC4923889 fatcat:eajrdxodlvhr7psnpzbedvvpjy

Quantum discord between two moving two-level atoms

Yao-Hua Hu, Mao-Fa Fang
2012 Open Physics  
AbstractConsidering a double JC model, this paper investigates the quantum discord dynamics of two isolated moving two-level atoms each interacting with a single-mode thermal cavity field, and studies  ...  discord still can capture the quantum correlation between the two atoms when the entanglement is zero.  ...  In order to follow the entanglement dynamics of the two two-level atoms, we choose the Wootters entanglement measure [38, 39] , the concurrence C , defined as C = max(0 λ 1 − λ 2 − λ 3 − λ 4 ) (15) where  ... 
doi:10.2478/s11534-011-0076-6 fatcat:vs6esovdunaehh3xzua6w3qavm

Heralded generation of Bell states using atomic ensembles

David Shwa, Raphael D. Cohen, Alex Retzker, Nadav Katz
2013 Physical Review A. Atomic, Molecular, and Optical Physics  
We propose a scheme that utilizes the collective enhancement of a photonic mode inside an atomic ensemble together with a proper Zeeman manifold in order to achieve a heralded polarization entangled Bell  ...  The entanglement is between two photons that are separated in time and can be used as a post selected deterministic source for applications such as quantum repeaters where a subsequent entanglement swapping  ...  A.R. also acknowledges the support of a Career Integration Grant (CIG), Grant No. 321798 IonQuanSense FP7-PEOPLE-2012-CIG.  ... 
doi:10.1103/physreva.88.063844 fatcat:26fskujcmrf7ve6zpmsncpiwaa

Atoms versus photons as carriers of quantum states

Smail Bougouffa, Zbigniew Ficek
2013 Physical Review A. Atomic, Molecular, and Optical Physics  
The problem of the complete transfer of quantum states and entanglement in a four qubits system composed of two single-mode cavities and two two-level atoms is investigated.  ...  Simple expressions are derived for the conditions for the complete transfer of quantum states and entanglement.  ...  cavity modes are in the maximally entangled two-photon state and the atoms are in their ground states.  ... 
doi:10.1103/physreva.88.022317 fatcat:452xr32zsjenbe5fwc6r2xr7ui

Nonadiabatic approach to entanglement distribution over long distances

Mohsen Razavi, Jeffrey H. Shapiro
2007 Physical Review A. Atomic, Molecular, and Optical Physics  
Entanglement distribution between trapped-atom quantum memories, viz. single atoms in optical cavities, is addressed.  ...  This loading efficiency is analytically studied for two-level, V-level, Λ-level, and double-Λ-level atomic configurations by means of a system-reservoir approach.  ...  That analysis results in a novel non-adiabatic approach to loading quantum memories with Λ and double-Λ atomic configurations.  ... 
doi:10.1103/physreva.75.032318 fatcat:ga5np775a5chjjhubhjqzzzlau

Ground-state blockade of Rydberg atoms and application in entanglement generation

X. Q. Shao, D. X. Li, Y. Q. Ji, J. H. Wu, X. X. Yi
2017 Physical Review A  
As applications, we discuss in detail the feasibility of preparing two-atom and three-atom entanglement with ground-state blockade in closed system and open system, respectively, which shows that a high  ...  Inspired by the quantum Zeno effect, the strong Rydberg antiblockade interaction plays a role in frequently measuring one ground state of two, leading to a blockade effect for double occupation of the  ...  Then we investigate the robustness for preparation of the maximally Bell entangled state based on the ground-state Rybderg blockade in a closed system and in an open system, respectively in Secs.  ... 
doi:10.1103/physreva.96.012328 fatcat:hrymqbn55fdu3bvwm26qqxhuqy

Multiphoton interaction of a qutrit with single-mode quantized field in the ultrastrong and deep strong coupling regimes

Hamlet K. Avetissian, Ara K. Avetissian, Garnik F. Mkrtchian, Oleg V. Kibis
2015 Journal of Nanophotonics  
We consider multiphoton dynamics of a quantum system composed of a three-state atom (a qutrit) and a single-mode photonic field in the ultrastrong and deep strong coupling regimes, when the coupling strength  ...  We assume a qutrit to be in a polar-Λ configuration in which two lower levels have mean dipole moments.  ...  In the present paper we consider a quantum system composed of a three-level artificial atom (qutrit) and a single-mode photonic field, i.e. harmonic oscillator, in the ultrastrong and deep strong coupling  ... 
doi:10.1117/1.jnp.9.093064 fatcat:2t7eijwh4bctxhzsnyockameea
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