# Quantum correlations and global coherence in distributed quantum computing

@article{Shahandeh2019QuantumCA, title={Quantum correlations and global coherence in distributed quantum computing}, author={Farid Shahandeh and Austin P. Lund and Timothy C. Ralph}, journal={Physical Review A}, year={2019} }

Deviations from classical physics when distant quantum systems become correlated are interesting both fundamentally and operationally. There exist situations where the correlations enable collaborative tasks that are impossible within the classical formalism. Here, we consider the efficiency of quantum computation protocols compared to classical ones as a benchmark for separating quantum and classical resources and argue that the computational advantage of collaborative quantum protocols in the…

## 15 Citations

Generalized Quantum Correlations in Discrete Variable Systems

- Computer ScienceSpringer Theses
- 2019

This chapter deals with the development of the novel notion of generalized quantum correlations within discrete variable systems through a toy model and defines the notion of quantum correlations and provides analysis of its feasibility and operational significance.

Classical evolution in quantum systems

- Physics
- 2020

For studying quantum phenomena in time, it is vital to have a profound understanding of the classical dynamics. For this reason, we derive equations of motions describing the classical propagation of…

Time dynamics of quantum coherence and monogamy in a non-Markovian environment

- Mathematics, MedicineScientific Reports
- 2019

The local coherence is found to be much more robust under the environmental coupling due to an effective smaller coupling to the reservoir, allowing for a characterization of a quantum state in terms of a coherence tuple on a multipartite state simply by examining various combinations of reservoir couplings.

Benchmarking the Future-Proofedness of Photonic Quantum Systems

- Physics, Computer Science
- 2020

This experimental contribution benchmarks the time-multiplexing framework that includes a high-performance source of multi-photon states and a large multiplexing network, together with unique detectors with high photon-number resolution, readily available for distributing quantum light and measuring complex quantum correlations.

Quantum correlation swapping between Werner derivatives

- PhysicsLaser Physics Letters
- 2021

Werner derivatives are a special kind of mixing states that originate from the Werner state due to unitary evolutions. In this paper, quantum correlation (QC) swapping between two Werner derivatives…

Quantum coherence measurement of qudit systems using three-dimensional photonic circuits

- Physics
- 2020

Knowing that quantum coherence plays a central role in quantum phenomena, we propose, in this work, three-dimensional photonic circuits with compact designs that allow measurement of the quantum…

Properties of Pancharatnam Phase and Entanglement of a Five-Level Atom Interacting with a Squeezed Field

- Physics
- 2021

We introduce a quantum scheme where a single five-level atom interacts with a single-mode cavity field by a time-dependent coupling. During the interaction, the temporal behavior of the quantum…

Nonreciprocal single-photon router in quantum networks

- Physics
- 2021

High-efficiency single-photon routing of photon signals between different quantum channels is of great importance for the quantum networks with the ability to coherently transfer quantum states…

Quantum correlations for anonymous metrology

- Computer Science, PhysicsQuantum
- 2019

It is shown that quantum correlations are resources for this task when Alice and Bob do not trust the devices in their labs, and different kinds of quantum correlations according to the level of desired security are distinguished.

## References

SHOWING 1-10 OF 63 REFERENCES

Quantum Correlations in Nonlocal BosonSampling

- Medicine, Computer SciencePhysical review letters
- 2017

This work reports on a distributed quantum computation protocol in which the input and output quantum states are considered to be classically correlated in quantum informatics, and shows that the correlations between the outcomes of the measurements on the output state cannot be efficiently simulated using classical algorithms.

Experimental quantum computing without entanglement.

- Physics, MedicinePhysical review letters
- 2008

The results show that even fully separable, highly mixed, states can contain intrinsically quantum mechanical correlations and that these could offer a valuable resource for quantum information technologies.

Converting Coherence to Quantum Correlations.

- Physics, MedicinePhysical review letters
- 2016

It is shown how the interplay between quantum coherence consumption and creation of quantum discord works in the preparation of multipartite quantum correlated states and in the model of deterministic quantum computation with one qubit.

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

- Physics, Mathematics
- 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…

Quantum processes which do not use coherence

- Physics
- 2015

A major signature of quantum mechanics beyond classical physics is coherence, the existence of superposition states. The recently developed resource theory of quantum coherence allows the…

Quantum correlations in composite systems

- Physics
- 2017

We study emerging notions of quantum correlations in compound systems. Based on different definitions of quantumness in individual subsystems, we investigate how they extend to the joint description…

Relating the Resource Theories of Entanglement and Quantum Coherence.

- Computer Science, PhysicsPhysical review letters
- 2016

This Letter analyzes the coherence and entanglement trade-offs in the tasks of state formation and resource distillation and introduces a new LIOCC monotone that completely characterizes a state's optimal rate of bipartite coherence distillation.

Role of entanglement and correlations in mixed-state quantum computation

- Physics
- 2007

In a quantum computation with pure states, the generation of large amounts of entanglement is known to be necessary for a speedup with respect to classical computations. However, examples of quantum…

Measuring Quantum Coherence with Entanglement.

- Computer Science, MedicinePhysical 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.

Unified view of quantum correlations and quantum coherence

- Physics
- 2016

In this paper, we argue that quantum coherence in a bipartite system can be contained either locally or in the correlations between the subsystems. The portion of quantum coherence contained within…