Related papers: Coherent phase control of two-color continuous var…
We proposed a scheme of continuous-variable quantum key distribution, in which the bright Einstein-Podolsky-Rosen entangled optical beams are utilized. The source of the entangled beams is placed inside the receiving station, where half of…
We analyse two classes of Einstein-Podolsky-Rosen (EPR)-steering inequalities, the violation of which can be used to demonstrate EPR-steering with an entangled two-qubit Werner state: linear inequalities and quadratic inequalities. We…
We consider two systems A and B that share Einstein-Podolsky-Rosen (EPR) steering correlations and study how these correlations will decay, when each of the systems are independently coupled to a reservoir. EPR steering is a directional…
In 1935 Schr\"odinger introduced the terms entanglement and steering in the context of the famous gedanken experiment discussed by Einstein, Podolsky, and Rosen (EPR). Here, we report on a sixfold increase of the observed EPR-steering…
Entangled photon sources (EPS), the major building block for a variety of quantum communication protocols, are commonly developed by utilizing the spontaneous parametric down-conversion (SPDC) in $\chi^{2}$ nonlinear bulk optical materials.…
We propose and analyse a pumped Bose-Hubbard dimer as a source of continuous-variable Einstein-Podolsky-Rosen (EPR) steering with non-Gaussian statistics. We use the truncated Wigner representation to calculate third and fourth order…
Multi-mode entanglement is one of the critical resource in quantum information technology. Generating large scale multi-mode entanglement state by coherently combining time-delayed continuous variables Einstein-Podolsky-Rosen pairs with…
We propose a scheme for the secure direct communication based on the entangled phase-coherent states, which shows an elevated level of confidentiality. The protocol gives a simultaneous security control for every bit of transferred…
Integrated optics allow the generation and control of increasingly complex photonic states on chip based architectures. Here, we implement two entangled qutrits - a 9-dimensional quantum system - and demonstrate an exceptionally high degree…
We develop a comprehensive model for the effective two-photon density matrix produced by a parametric source of entangled photon pairs under a variety of detector configurations commonly seen in a laboratory setting: two and four photon…
Quantum entanglement is an essential ingredient for the absolute security of quantum communication. Generation of continuous-variable entanglement or two-mode squeezing between light fields based on the effect of electromagnetically induced…
Einstein-Podolsky-Rosen (EPR) steering is one of the most intriguing features of quantum mechanics and an important resource for quantum communication. For practical applications, it remains a challenge to protect EPR steering from…
The Stokes and anti-Stokes components of the spectrum of resonance fluorescence of a single trapped atom, which originate from the mechanical coupling between the scattered photons and the quantized motion of the atomic center of mass,…
Evidence for Bell's nonlocality is so far mainly restricted to microscopic systems, where the elements of reality that are negated predetermine results of measurements to within one spin unit. Any observed nonlocal effect (or lack of…
A protocol for quantum secure direct communication using blocks of EPR pairs is proposed. A set of ordered $N$ EPR pairs is used as a data block for sending secret message directly. The ordered $N$ EPR set is divided into two particle…
Multi-color entangled states of light including low-loss optical fiber transmission and atomic resonance frequencies are essential resources for future quantum information network. We present the experimental achievement on the three-color…
Einstein-Rosen-Podolsky (EPR) steering or quantum steering describes the "spooky-action-at-a-distance" that one party is able to remotely alter the states of the other if they share a certain entangled state. Generally, it admits an…
In this paper, we propose a method to generate entangled coherent states between two spatially separated atomic Bose-Einstein condensates (BECs) via the technique of the electromagnetically induced transparency (EIT). Two strong coupling…
Intense spatio-spectral twin beams generated in the regime with pump depletion are analyzed applying a suggested quantum model that treats the signal, idler and pump fields in the same way. The model assumes the signal and idler fields in…
We present a protocol for quantum key distribution using discrete modulation of coherent states of light. Information is encoded in the variable phase of coherent states which can be chosen from a regular discrete set ranging from binary to…