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Related papers: Entangled coherent states: teleportation and decoh…

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We consider the problem of bi-directional controlled quantum teleportation of information encoded in phase opposite coherent state among two distant partners Alice and Bob, with the consent of controller, Charlie. We use five-mode…

Quantum Physics · Physics 2021-12-15 Ravi Kamal Pandey , Phool Singh Yadav , Ranjana Prakash , Hari Prakash

We report the experimental realization of teleporting an entangled qubit. The qubit is physically implemented by a two-dimensional subspace of states of a mode of the electromagnetic field, specifically, the space spanned by the vacuum and…

Quantum Physics · Physics 2007-05-23 Egilberto Lombardi , Fabio Sciarrino , Sandu Popescu , Francesco De Martini

A new concept of qubits is given by considering entanglement of ordinary quibits with quantum measuring devices (micro-detectors). They are called stochastic qubits since they are generalized coherent states used in the stochastic (phase…

Quantum Physics · Physics 2015-02-25 Abdallah Smida , Mahmoud Hachemane , Amel-Hiba Hamici

Optical coherent states are classical light fields with high purity, and are essential carriers of information in optical networks. If these states could be controlled in the quantum regime, allowing for their quantum superposition…

Quantum Physics · Physics 2013-11-13 Jonas S. Neergaard-Nielsen , Yujiro Eto , Chang-Woo Lee , Hyunseok Jeong , Masahide Sasaki

The entanglement of two qubits, each defined as an effective two-level, spin 1/2 system, is investigated for the case that the qubits interact via a Heisenberg XY interaction and are subject to decoherence due to population relaxation and…

Quantum Physics · Physics 2007-05-23 Jin Wang , Herman Batelaan , Jeremy Podany , Anthony F. Starace

Recently, we have shown theoretically [1] as well as experimentally [2] how the phase of an electromagnetic field can be determined by measuring the population of either of the two states of a two-level atomic system excited by this field,…

Quantum Physics · Physics 2007-05-23 M. S. Shahriar , P. Pradhan , V. Gopal , G. Pati , G. C. Cardoso

We find that quantum teleportation, using the thermally entangled state of two-qubit Heisenberg XX chain as a resource, with fidelity better than any classical communication protocol is possible. However, a thermal state with a greater…

Quantum Physics · Physics 2009-11-07 Ye Yeo

Physical systems usually exhibit quantum behavior, such as superpositions and entanglement, only when they are sufficiently decoupled from a lossy environment. Paradoxically, a specially engineered interaction with the environment can…

Decoherence is one of the main obstacles in long-distance quantum communication. Recently, the theoretical work of Fr\"{o}wis and W. D\"{u}r (Phys. Rev. Lett. \textbf{106}, 110402 (2011)) and the experiment of Lu \emph{et al.} (Nat. Photon.…

Quantum Physics · Physics 2014-05-13 Yu-Bo Sheng , Lan Zhou

Quantum teleportation of qudits is revisited. In particular, we analyze the case where the quantum channel corresponds to a non-maximally entangled state and show that the success of the protocol is directly related to the problem of…

Quantum Physics · Physics 2009-11-10 L. Roa , A. Delgado , I. Fuentes-Guridi

Exploiting the cluster of three Bell coherent-states as quantum channel, we presented a scheme wherein quantum-informations encoded in three arbitrary superposed coherent states, i.e., Schrodinger Cat coherent-states are simultaneously…

Quantum Physics · Physics 2024-03-06 Ankita Pathak , Ravi S. Singh

Using Lindblad approach to study decoherence of quantum systems, we study the decoherence and decay of entangled states, formed by two basic states of a chain of thee qubits. We look on these states for a possible regular dependence on…

Quantum Physics · Physics 2015-03-13 Gustavo V. Lopez , Gustavo Montes

Quantum coherence and quantum entanglement are two different manifestations of the superposition principle. In this article we show that the right choice of basis to be used to estimate coherence is the separable basis. The quantum…

We consider quantum teleportation using the thermally entangled state of a three-qubit Heisenberg XX ring as a resource. Our investigation reveals interesting aspects of quantum entanglement not reflected by the pairwise thermal concurrence…

Quantum Physics · Physics 2013-05-29 Ye Yeo

We show how entangled qubits can be encoded as entangled coherent states of two-dimensional centre-of-mass vibrational motion for two ions in an ion trap. The entangled qubit state is equivalent to the canonical Bell state, and we introduce…

Quantum Physics · Physics 2009-10-31 W. J. Munro , G. J. Milburn , B. C. Sanders

We introduce a quantum teleportation scheme that can transfer a macroscopic spin coherent state between two locations. In the scheme a large number of copies of a qubit, such as realized in a coherent two-component Bose-Einstein condensate,…

Quantum Physics · Physics 2015-06-15 Alexey Pyrkov , Tim Byrnes

We present a setup for a direct, total teleportation of a single-particle entangled state. Our scheme consists of a parametric down-conversion source, which emits a pair of entangled photons, and a dual Bell measurement system with two beam…

Quantum Physics · Physics 2009-11-07 Hai-Woong Lee

This paper presents properties of the so-called quasi-Bell states: entangled states written as superpositions of nonorthogonal states. It is shown that a special class of those states, namely entangled coherent states, are more robust…

Quantum Physics · Physics 2007-05-23 Osamu Hirota , Steven J. van Enk , Kazuo Nakamura , Masaki Sohma , Kentaro Kato

This paper proposes a scheme for teleporting an arbitrary coherent superposition state of two equal-amplitude and opposite-phase squeezed vacuum states (SVS) via a symmetric 50/50 beam splitter and photodetectors. It is shown that the…

Quantum Physics · Physics 2007-05-23 Xin-Hua Cai , Le-Man Kuang

We compare effects of decoherence and detection inefficiency on entangled coherent states (ECSs) and entangled photon pairs (EPPs), both of which are known to be particularly useful for quantum information processing (QIP). When decoherence…

Quantum Physics · Physics 2011-02-08 Kimin Park , Hyunseok Jeong