Related papers: Entanglement swapping between discrete and continu…
The hybrid entangled states generated, e.g., in a trapped-ion or atom-cavity system, have exactly one ebit of entanglement, but are not maximally entangled. We demonstrate this by showing that they violate, but in general do not maximally…
A basic problem of quantum communication is to generate entangled states between distant sites. Using entanglement swapping, we are able to generate an entangled state of the desired distance from connecting many short distance entangled…
We determine the two mode fock state of the radiation emitted by $V$ type three level atomic systems using the method of tomography described in our previous work. Utilizing the knowledge of the atomic/two photon state we provide a complete…
The global quantum network requires the distribution of entangled states over long distances, with significant advances already demonstrated using entangled polarisation states, reaching approximately 1200 km in free space and 100 km in…
We investigate the dynamical behavior of the atom-photon entanglement in a V-type three-level quantum system using the atomic reduced entropy. It is shown that an atom and photons are entangled at the steady-state; however disentanglement…
We propose a scheme for distributing continuous variable entanglement originally established among a pair of mode between a set of four orthogonal co-propagating modes. This is accomplished by exploiting the possibility of coupling…
High-dimensional entangled states offer higher information capacity and stronger resilience to noise compared with two-dimensional systems. However, the large number of modes and sensitivity to random rotations complicate experimental…
We analyse the distribution of secure keys using quantum cryptography based on the continuous variable degree of freedom of entangled photon pairs. We derive the information capacity of a scheme based on the spatial entanglement of photons…
We report on theoretical and experimental demonstration of high-efficiency coupling of two-photon entangled states produced in the nonlinear process of spontaneous parametric down conversion into a single-mode fiber. We determine…
We study the accumulation of entanglement in a memory device built out of two continuous variable (CV) systems. We address the case of a qubit mediating an indirect joint interaction between the CV systems. We show that, in striking…
Efficient interfaces between photons and quantum emitters form the basis for quantum networks and enable nonlinear optical devices operating at the single-photon level. We demonstrate an integrated platform for scalable quantum…
We propose a deterministic scheme for teleporting an unknown qubit through continuous-variable entangled states in superconducting circuits. The qubit is a superconducting two-level system and the bipartite quantum channel is a photonic…
The entanglement transfer from electrons localized in a pair of quantum dots to circularly polarized photons is governed by optical selection rules, enforced by conservation of angular momentum. We point out that the transfer can not be…
We present a scheme to generate continuous variable bipartite entanglement between two optical modes in a hybrid optical-microwave-plasmonic graphene waveguide system. In this scheme, we exploit the interaction of two light fields coupled…
We consider the quantum cloning of continuous variable entangled states. This is achieved by introducing two symmetric entanglement cloning machines (or e-cloners): a local e-cloner and a global e-cloner; where we look at the preservation…
Quantum transduction between microwave and optics can be realized by quantum teleportation if given reliable microwave-optical entanglement, namely entanglement-based quantum transduction. To realize this protocol, an entangled source with…
We present a scheme for broadcasting of continuous variable entanglement. We show how an initial two-mode squeezed state of the electromagnetic field shared by two distant parties can be broadcasted into two nonlocal bipartite entangled…
We study the entanglement distillation in continuous variable systems when a photon replacement protocol is employed. A cascaded protocol is studied and we find that the resultant entanglement increases by increasing the number of…
Many different quantum information communication protocols such as teleportation, dense coding and entanglement based quantum key distribution are based on the faithful transmission of entanglement between distant location in an optical…
We present a proposal for entanglement purification of the continuous-variable quantum state of two propagating optical fields. The scheme is based on letting each field interact with a local node, an atomic ensemble, whose internal…