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Related papers: Continuous-variable Werner state: separability, no…

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We consider a special kind of mixed states -- a {\it Werner derivative}, which is the state transformed by nonlocal unitary -- local or nonlocal -- operations from a Werner state. We show the followings. (i) The amount of entanglement of…

Quantum Physics · Physics 2009-11-06 Tohya Hiroshima , Satoshi Ishizaka

The dynamics of entanglement between two-level atoms immersed in a common photon reservoir at finite temperature is investigated. It is shown that in the regime of strong correlations there are nontrivial asymptotic states which can be…

Quantum Physics · Physics 2015-05-14 Lech Jakobczyk

We investigate continuous variable quantum teleportation using non-Gaussian states of the radiation field as entangled resources. We compare the performance of different classes of degaussified resources, including two-mode photon-added and…

Quantum Physics · Physics 2007-08-03 F. Dell'Anno , S. De Siena , L. Albano Farias , F. Illuminati

We propose a method for quantum enhanced phase estimation based on continuous variable (CV) quantum teleportation. The phase shift probed by a coherent state can be enhanced by repeatedly teleporting the state back to interact with the…

We give a protocol and criteria for demonstrating unconditional teleportation of continuous-variable entanglement (i.e., entanglement swapping). The initial entangled states are produced with squeezed light and linear optics. We show that…

Quantum Physics · Physics 2009-10-31 P. van Loock , Samuel L. Braunstein

We study the possibility to teleport an unkown quantum state onto the vibrational degree of freedom of a movable mirror. The quantum channel between the two parties is established by exploiting radiation pressure effects.

Quantum Physics · Physics 2007-05-23 Stefano Mancini , David Vitali , Paolo Tombesi

We address an open question about the existence of entangled continuous-variable (CV) Werner states with positive partial transpose (PPT). We prove that no such state exists by showing that all PPT CV Werner states are separable. The…

Quantum Physics · Physics 2014-03-28 Daniel McNulty , Richard Tatham , Ladislav Mišta

This paper discusses methods for the optical teleportation of continuous variable polarisation states. We show that using two pairs of entangled beams, generated using four squeezed beams, perfect teleportation of optical polarisation…

Quantum Physics · Physics 2009-11-10 A. Dolinska , B. C. Buchler , P. K. Lam , T. C. Ralph , W. P. Bowen

In this paper we extend our recent results for quantum teleportation of single qubit pure information state using non-maximally entangled pure state resource [Quantum Inf Process, 11 (2012) 1251] to the case of a general mixed information…

Quantum Physics · Physics 2013-05-21 Hari Prakash , Vikram Verma

In this paper, we examine and compare two fundamentally different teleportation schemes; the well-known continuous variable scheme by Vaidman, Braunstein and Kimble (VBK), and a recently proposed hybrid scheme by Andersen and Ralph (AR). We…

Quantum Physics · Physics 2014-05-29 Ioannis Kogias , Sammy Ragy , Gerardo Adesso

We propose two probabilistic entanglement concentration schemes for a single copy of two-mode squeezed vacuum state. The first scheme is based on the off-resonant interaction of a Rydberg atom with the cavity field while the second setup…

Quantum Physics · Physics 2012-08-27 Jaromir Fiurasek , Ladislav Mista, , Radim Filip

Teleportation of optical field states (as continuous quantum variables) is usually described in terms of Wigner functions. This is in marked contrast to the theoretical treatment of teleportation of qubits. In this paper we show that by…

Mathematical Physics · Physics 2009-06-11 S. Nagamachi , E. Brüning

We introduce a new class of continuous-variable (CV) multipartite entangled states, the CV cluster states, which might be generated from squeezing and kerr-like interaction. The entanglement properties of these states are studied in terms…

Quantum Physics · Physics 2015-06-26 Jing Zhang

We investigate permutation-invariant continuous variable quantum states and their covariance matrices. We provide a complete characterization of the latter with respect to permutation-invariance, exchangeability and representing convex…

Quantum Physics · Physics 2009-11-13 Robert Koenig , Michael M. Wolf

We suggest a scheme of using two-mode squeezed vacuum for conditional teleportation of quantum states of optical field. Alice mixes the input state with one of the squeezed modes on another squeezing device and detects the output photon…

Quantum Physics · Physics 2009-11-06 J. Clausen , T. Opatrny , D. -G. Welsch

We demonstrate Werner-like polarization-entangled state generation disapproving local hidden variable theory from a single semiconductor quantum dot. By exploiting tomographic analysis with temporal gating, we find biphoton states are…

Quantum Physics · Physics 2015-06-03 H. Kumano , H. Nakajima , T. Kuroda , T. Mano , K. Sakoda , I. Suemune

We present an analysis of squeezed single photon states as a resource for teleportation of coherent state qubits and propose proof-of-principle experiments for the demonstration of coherent state teleportation and entanglement swapping. We…

Quantum Physics · Physics 2010-06-04 Agata M Branczyk , T. C. Ralph

We propose a reliable entanglement measure for a two-mode squeezed thermal state of the quantum electromagnetic field in terms of its Bures distance to the set of all separable states of the same kind. The requisite Uhlmann fidelity of a…

Quantum Physics · Physics 2007-05-23 Paulina Marian , Tudor A. Marian , Horia Scutaru

A quantum channel is derived for continuous variable teleportation which is performed by means of an arbitrary entangled state and the standard protocol. When a Gaussian entangled state such as a two-mode squeezed-vacuum state is used, the…

Quantum Physics · Physics 2009-11-07 Masashi Ban , Masahide Sasaki , Masahiro Takeoka

We investigate the role of quadrature squeezing in the quantum teleportation protocol for coherent states, using non-Gaussian resource states. For the two-mode systems, the non-Gaussian resource states that we use are obtained by an…

Quantum Physics · Physics 2025-02-25 Mohak Sharma , Chandan Kumar , Shikhar Arora , Arvind