English
Related papers

Related papers: Quantum secure identification using entanglement a…

200 papers

Entangled states that cannot be distilled to maximal entanglement are called bound entangled and they are often viewed as too weak to break the limitations of classical models. Here, we show a strongly contrasting result: that bound…

Quantum Physics · Physics 2026-03-09 Armin Tavakoli , Carles Roch i Carceller , Lucas Tendick , Tamás Vértesi

Quantum entanglement of pure states of a bipartite system is defined as the amount of local or marginal ({\em i.e.}referring to the subsystems) entropy. For mixed states this identification vanishes, since the global loss of information…

Quantum Physics · Physics 2007-05-23 Gerardo Adesso , Alessio Serafini , Fabrizio Illuminati

We propose a new cryptographic protocol. It is suggested to encode information in ordinary binary form into many-qubit entangled states with the help of a quantum computer. A state of qubits (realized, e.g., with photons) is transmitted…

Quantum Physics · Physics 2016-09-08 K. V. Bayandin , G. B. Lesovik

Any experiment attempting to verify the presence of entanglement in a physical system can only generate a finite amount of data. The statement that entanglement was present in the system can thus never be issued with certainty, requiring…

Entanglement has evolved from an enigmatic concept of quantum physics to a key ingredient of quantum technology. It explains correlations between measurement outcomes that contradict classical physics, and has been widely explored with…

Quantum Physics · Physics 2024-06-05 Philip Thomas , Leonardo Ruscio , Olivier Morin , Gerhard Rempe

We investigate the use of noisy entanglement as a resource in classical communication via a quantum channel. In particular, we are interested in the question whether for any entangled state, including bound entangled states, there exists a…

Quantum Physics · Physics 2019-07-31 Stefan Bäuml , Andreas Winter , Dong Yang

The efficacies of maximally and that of non-maximally entangled mixed states as teleportation channels have been studied. A new class of non-maximally entangled mixed states have been proposed also. Their advantages as quantum teleportation…

Quantum Physics · Physics 2020-07-22 Sovik Roy

Entanglement and coherence are fundamental properties of quantum systems, promising to power near future quantum technologies, such as quantum computation, quantum communication and quantum metrology. Yet, their quantification, rather than…

Continuous-variable quantum states are of particular importance in various quantum information processing tasks including quantum communication and quantum sensing. However, a bottleneck has emerged with the fast increasing in size of the…

Quantum Physics · Physics 2021-10-13 Ye-Chao Liu , Jiangwei Shang , Xiangdong Zhang

Quantum thermodynamics and quantum entanglement represent two pivotal quantum resource theories with significant relevance in quantum information science. Despite their importance, the intricate relationship between these two theories is…

Quantum Physics · Physics 2025-03-26 Ray Ganardi , Piotr Masajada , Moein Naseri , Alexander Streltsov

We show that the usefulness of a state as an activator in teleportation protocols is equivalent to the robustness of its entanglement to noise. The robustness of entanglement of a bi-partite state is linked to the maximum increase in the…

Quantum Physics · Physics 2010-03-10 Fernando G. S. L. Brandao

Entangled physical systems are an important resource in quantum information. Some authors claim that in fact all quantum states are entangled. In this paper we show that this claim is incorrect and we discuss in operational way differences…

Quantum Physics · Physics 2016-10-07 Marian Kupczynski

An iterative random procedure is considered allowing an entanglement purification of a class of multi-mode quantum states. In certain cases, a complete purification may be achieved using only a single signal state preparation. A physical…

Quantum Physics · Physics 2009-11-10 J Clausen , L Knoell , D-G Welsch

Quantum teleportation is the process of transferring quantum information using classical communication and pre-shared entanglement. This process can benefit from the use of catalysts, which are ancillary entangled states that can enhance…

In the realm of quantum information processing, the efficient characterization of entangled states poses an overwhelming challenge, rendering the traditional methods including quantum tomography unfeasible and impractical. To tackle this…

Quantum Physics · Physics 2025-12-09 Ye-Chao Liu , Jiangwei Shang

This note shows how quantum entanglement may be simulated in classical computing. The simulated entanglement protocol is implemented using oblivious transfer in the simplest case and other many-to-one mappings in more general cases. For the…

Quantum Physics · Physics 2013-01-11 Subhash Kak

We discuss aspects of secure quantum communication by proposing and analyzing a quantum analog of the Vernam cipher (one-time-pad). The quantum Vernam cipher uses entanglement as the key to encrypt quantum information sent through an…

Quantum Physics · Physics 2007-05-23 D. W. Leung

A novel secure communication protocol is presented, based on an entangled pair of qubits and allowing asymptotically secure key distribution and quasi-secure direct communication. Since the information is transferred in a deterministic…

Quantum Physics · Physics 2009-11-07 Kim Bostroem , Timo Felbinger

The ability to filter quantum states is a key capability in quantum information science and technology, in which one-qubit filters, or polarizers, have found wide application. Filtering on the basis of entanglement requires extension to…

Associating a physical process with the pure entangled state 1/sqrt 2 (|00> + |11>) is an idealization unless the pair is so prepared using an appropriate quantum gate operating on a known state. Questions related to the reference frame for…

Quantum Physics · Physics 2007-05-23 Subhash Kak