# Quantum correlations in separable multi-mode states and in classically entangled light.

@article{Korolkova2019QuantumCI, title={Quantum correlations in separable multi-mode states and in classically entangled light.}, author={Natalia Korolkova and Gerd Leuchs}, journal={Reports on progress in physics. Physical Society}, year={2019}, volume={82 5}, pages={ 056001 } }

In this review we discuss intriguing properties of apparently classical optical fields, that go beyond purely classical context and allow us to speak about quantum characteristics of such fields and about their applications in quantum technologies. We briefly define the genuinely quantum concepts of entanglement and steering. We then move to the boarder line between classical and quantum world introducing quantum discord, a more general concept of quantum coherence, and finally a controversial…

## 31 Citations

Quantum concepts in optical polarization

- Physics
- 2020

We comprehensively review the quantum theory of the polarization properties of light. In classical optics, these traits are characterized by the Stokes parameters, which can be geometrically…

Oscillating between classically entangled state and separable state: an analogy between classical and quantum optics

- PhysicsJournal of the Optical Society of America B
- 2020

In this paper, we study the possible realization of a classical system with quantum characteristics on the level of classical optics. Indeed, following Arrizon et al. [J. Opt. Soc. Am. A32, 1140…

Classical Optical Analogue of Quantum Discord

- Physics
- 2022

: Quantum discord has been shown to be a resource for quantum advantage in addition to quantum entanglement. While many experiments have demonstrated classical analogies of entanglement, none have…

Single‐Particle Entanglement

- PhysicsAdvanced Quantum Technologies
- 2020

This review is about single‐particle entanglement. Entanglement occurs when the state of a quantum system with at least two degrees of freedom has a particular non‐separable form. In the case of…

Creation and control of high-dimensional multi-partite classically entangled light

- PhysicsLight, science & applications
- 2021

This work demonstrates the first vectorially structured light created and fully controlled in eight dimensions, a new state-of-the-art state of the art, and externally modulates the beam to control, for the first time, the complete set of classical Greenberger–Horne–Zeilinger states in paraxial structured light beams.

Single-photon steering

- Physics
- 2021

According to Schrödinger, the laws of quantum mechanics obliges us to admit that by suitable measurement taken on one of the two system only the state of the other system can not only be determined…

Roots of Quantum Computational Supremacy: Superposition? Entanglement? Or Complementarity?

- Physics
- 2019

The recent Google’s claim on breakthrough in quantum computing is a gong signal for further analysis of foundational roots of (possible) superiority of some quantum algorithms over the corresponding…

Roots of quantum computing supremacy: superposition, entanglement, or complementarity?

- Computer Science
- 2021

A critical analysis of what is commonly referred to as entanglement and quantum nonlocality and whether or not these concepts may be the basis of quantum superiority is start with a critical analysis.

Graded-index optical fiber emulator of an interacting three-atom system: illumination control of particle statistics and classical non-separability

- PhysicsQuantum
- 2019

We show that a system of three trapped ultracold and strongly interacting atoms in one-dimension can be emulated using an optical fiber with a graded-index profile and thin metallic slabs. While the…

Old experiments in new light: Young's double-slit and Stern-Gerlach experiments in liquid crystal microcavities

- Physics
- 2021

Spin-orbit interactions which couple spin of a particle with its momentum degrees of freedom lie at the center of spintronic applications. Of special interest in semiconductor physics are Rashba and…

## References

SHOWING 1-10 OF 123 REFERENCES

The classical-quantum boundary for correlations: Discord and related measures

- Physics
- 2012

One of the best signatures of nonclassicality in a quantum system is the existence of correlations that have no classical counterpart. Different methods for quantifying the quantum and classical…

Measures and applications of quantum correlations

- Physics, Computer Science
- 2016

This work gives an overview of the current quest for a proper understanding and characterisation of the frontier between classical and quantum correlations (QCs) in composite states, and focuses on various approaches to define and quantify general QCs, based on different yet interlinked physical perspectives.

Quantum Discord and its Role in Quantum Information Theory

- Physics, Computer Science
- 2014

This work presents quantum discord and general quantum correlations, and discusses three applications which are based on this new type of correlations: remote state preparation, entanglement distribution, and transmission of correlations.

Entanglement in Classical Optics

- Physics
- 2013

The emerging field of entanglement or nonseparability in classical optics is reviewed, and its similarities with and differences from quantum entanglement clearly pointed out through a recapitulation…

Using measurement-induced disturbance to characterize correlations as classical or quantum

- Physics
- 2008

In contrast to the seminal entanglement-separability paradigm widely used in quantum information theory, we introduce a quantum-classical dichotomy in order to classify and quantify statistical…

Measuring Quantum Coherence with Entanglement.

- PhysicsPhysical review letters
- 2015

This work demonstrates the usefulness of the approach by proving that the fidelity-based geometric measure of coherence is a full convex coherence monotone, and deriving a closed formula for it on arbitrary single-qubit states.

Colloquium: quantum coherence as a resource

- Physics
- 2017

The coherent superposition of states, in combination with the quantization of observables, represents one of the most fundamental features that mark the departure of quantum mechanics from the…

Single- and two-mode quantumness at a beam splitter

- Physics
- 2015

In the context of bipartite bosonic systems, two notions of classicality of correlations can be dened: P -classicality, based on the properties of the Glauber-Sudarshan P -function; and…

Introductory quantum optics

- Physics
- 2004

This book provides an elementary introduction to the subject of quantum optics, the study of the quantum mechanical nature of light and its interaction with matter. The presentation is almost…

Entanglement beating in free space through spin–orbit coupling

- PhysicsLight, science & applications
- 2018

Using local Bell states engineered from classical vector vortex beams with non-separable degrees of freedom, the so-called classically entangled states, it is demonstrated that the entanglement evolves during propagation, oscillating between maximally entangled and product states (purely scalar).