Related papers: Conditioning two-party quantum teleportation withi…
Quantum teleportation is one of the essential primitives of quantum communication. We suggest that any quantum teleportation scheme can be characterized by its efficiency, i.e. how often it succeeds to teleport, its fidelity, i.e. how well…
Open quantum systems and study of decoherence are important for our fundamental understanding of quantum physical phenomena. For practical purposes, there exists a large number of quantum protocols exploiting quantum resources, e.g.…
Recently Yu and Sun [Int. J. Theor. Phys. DOI 10.1007/s10773-014-2360-x] have presented probabilistic teleportation of 3-qubit cat state via 6-qubit cluster state. The success probability depends on absolute value of only two of the…
We present a novel, detailed study on the usefulness of three-mode Gaussian states states for realistic processing of continuous-variable quantum information, with a particular emphasis on the possibilities opened up by their genuine…
We show that the Innsbruck quantum teleportation experiment(Bouwmeester D et al, Nature 390, 575(1997)) can be modified by using the polarized beam splitter. In this modified scheme, Bob does not have to do any meassurement and an unknown…
We show how the partial entanglement inherent in a two mode squeezed vacuum state admits two different teleportation protocols. These two protocols refer to the different kinds of joint measurements that may be made by the sender. One…
We propose a multiparty quantum cryptographic protocol. Unitary operators applied by Bob and Charlie, on their respective qubits of a tripartite entangled state encodes a classical symbol that can be decoded at Alice's end with the help of…
We propose a simultaneous quantum secure direct communication scheme between one party and other three parties via four-particle GHZ states and swapping quantum entanglement. In the scheme, three spatially separated senders, Alice, Bob and…
We prove a theorem on direct relation between the optimal fidelity $f_{max}$ of teleportation and the maximal singlet fraction $F_{max}$ attainable by means of trace-preserving LQCC action (local quantum and classical communication). For a…
We give a (remote) quantum gambling scheme that makes use of the fact that quantum nonorthogonal states cannot be distinguished with certainty. In the proposed scheme, two participants Alice and Bob can be regarded as playing a game of…
The cryptographic protocol of coin tossing consists of two parties, Alice and Bob, that do not trust each other, but want to generate a random bit. If the parties use a classical communication channel and have unlimited computational…
We present a multi-partite protocol in a counterfactual paradigm. In counterfactual quantum cryptography, secure information is transmitted between two spatially separated parties even when there is no physical travel of particles…
We show how two distrustful parties, "Bob" and "Charlie", can share a secret key with the help of a mutually trusted "Alice", counterfactually - that is with no information-carrying particles travelling between any of the three parties.
We investigate the process of entanglement transfer from a three-mode quantized field to a system of three spatially separated qubits each one made of a two-level atom resonantly coupled to a cavity mode. The optimal conditions for…
We first consider teleportation of entangled states shared between Claire and Alice to Bob1 and Bob2 when Alice and the two Bobs share a single copy of a GHZ-class state and where {\it all} the four parties are at distant locations. We then…
Quantum teleportation is an essential application of quantum entanglement. The examination of teleportation fidelity in two-party standard teleportation schemes reveals a critical threshold distinguishing separable and entangled states. For…
We show how an interaction with the environment can enhance fidelity of quantum teleportation. To this end, we present examples of states which cannot be made useful for teleportation by any local unitary transformations; nevertheless,…
We show that {\it one} single-mode squeezed state distributed among $N$ parties using linear optics suffices to produce a truly $N$-partite entangled state for any nonzero squeezing and arbitrarily many parties. From this $N$-partite…
Quantum teleportation is a powerful protocol with applications in several schemes of quantum communication, quantum cryptography and quantum computing. The present work shows the required conditions for a two-qubit quantum gate to be…
Quantum teleportation of an unknown broadband electromagnetic field is investigated. The continuous-variable teleportation protocol by Braunstein and Kimble [Phys. Rev. Lett. {\bf 80}, 869 (1998)] for teleporting the quantum state of a…