Basis-independent quantum coherence and its distribution

Journal Article · Tue Oct 15 04:00:00 EDT 2019 · Annals of Physics

DOI:https://doi.org/10.1016/J.AOP.2019.04.020· OSTI ID:22848426

Radhakrishnan, Chandrashekar ^[1]; Ding, Zhe; Shi, Fazhan; Du, Jiangfeng ^[2]; Byrnes, Tim ^[3]

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1. New York University Shanghai, 1555 Century Ave, Pudong, Shanghai, 200122 (China)
2. CAS Key Laboratory of Microscale Magnetic Resonance and Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China)
3. State Key Laboratory of Precision Spectroscopy, School of Physical and Material Sciences, East China Normal University, Shanghai, 200062 (China)

We analyze a basis-independent definition of quantum coherence. The maximally mixed state is used as the reference state, which allows for a way of defining coherence that is invariant under arbitrary unitary transformations. Such a basis independent formulation is related to the purity of system rather than the superposition in a particular basis. The basis-independent approach is applied to finding the distribution of the coherence within a multipartite system, where the contributions due to correlations between the subsystems and within each subsystem are isolated. The use of the square root of the Jensen–Shannon divergence allows for inequality relations to be derived between these quantities, giving a geometrical picture within the Hilbert space of the system. We describe the relationship between the basis-independent and the basis-dependent approaches, and argue that many advantages exist for the former method. The formalism is illustrated with several numerical examples which show that the states can be characterized in a simple and effective manner.

• OSTI ID: 22848426
• Journal Information: Annals of Physics, Journal Name: Annals of Physics Vol. 409; ISSN 0003-4916; ISSN APNYA6
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CORRELATIONS
DISTRIBUTION
HILBERT SPACE
INFORMATION THEORY
MIXED STATES
QUANTUM DECOHERENCE
QUANTUM INFORMATION
QUANTUM SYSTEMS
TRANSFORMATIONS