Finite-temperature quantum discordant criticality
arXiv:2110.10597 · doi:10.1103/PhysRevB.105.075104
Abstract
In quantum statistical mechanics, finite-temperature phase transitions are typically governed by classical field theories. In this context, the role of quantum correlations is unclear: recent contributions have shown how entanglement is typically very short-ranged, and thus uninformative about long-ranged critical correlations. In this work, we show the existence of finite-temperature phase transitions where a broader form of quantum correlation than entanglement, the entropic quantum discord, can display genuine signatures of critical behavior. We consider integrable bosonic field theories in both two- and three-dimensional lattices, and show how the two-mode Gaussian discord decays algebraically with the distance even in cases where the entanglement negativity vanishes beyond nearest-neighbor separations. Systematically approaching the zero-temperature limit allows us to connect discord to entanglement, drawing a generic picture of quantum correlations and critical behavior that naturally describes the transition between entangled and discordant quantum matter.
arXiv comment8 pages, 7 figures
References in corpus (44)
- Separability Criterion for Density Matrices
- A computable measure of entanglement
- Introducing Quantum Discord
- Classical, quantum and total correlations
- Separability criterion and inseparable mixed states with positive partial transposition
- Necessary and sufficient condition for non-zero quantum discord
- Quantum discord for two-qubit X-states
- Quantum entanglement in condensed matter systems
- Classical Correlation and Quantum Discord in Critical Systems
- Almost all quantum states have non-classical correlations
- Quantum versus classical correlations in Gaussian states
- Gaussian quantum discord
- Entanglement negativity in quantum field theory
- Quantum correlations in spin chains at finite temperatures and quantum phase transitions
- Quantum discord and quantum phase transition in spin chains
- Measures and applications of quantum correlations
- Quantum discord for general two--qubit states: Analytical progress
- Computing quantum discord is NP-complete
- Symplectic invariants, entropic measures and correlations of Gaussian states
- The problem with the geometric discord
- Thermal and Magnetic Quantum Discord in Heisenberg models
- Quantum and classical thermal correlations in the XY spin-1/2 chain
- Genuine quantum correlations in quantum many-body systems: a review of recent progress
- Quantum discord for two-qubit X states: Analytical formula with very small worst-case error
- Driven Markovian Quantum Criticality
- Thermal state entanglement in harmonic lattices
- Optimality of Gaussian Discord
- Nonzero temperature Entanglement Negativity of quantum spin models: Area law, Linked Cluster Expansions and Sudden Death
- Long-range quantum discord in critical spin systems
- Thermal bound entanglement in macroscopic systems and area laws
- Scaling of quantum discord in spin models
- Geometric measures of quantum correlations: characterization, quantification, and comparison by distances and operations
- Singularity in Entanglement Negativity Across Finite Temperature Phase Transitions
- Ground state factorization and correlations with broken symmetry
- Criticality, factorization and long-range correlations in the anisotropic XY-model
- Entanglement Renyi negativity across a finite temperature transition: a Monte Carlo study
- Gaussian geometric discord
- Quantum variance: a measure of quantum coherence and quantum correlations for many-body systems
- Entanglement negativity and sudden death in the toric code at finite temperature
- Structure of Quantum Entanglement at a Finite Temperature Critical Point
- Hellinger distance as a measure of Gaussian discord
- Entanglement and classical fluctuations at finite-temperature critical points
- Coherence, entanglement and quantumness in closed and open systems with conserved charge, with an application to many-body localisation
- Quantum correlations, separability and quantum coherence length in equilibrium many-body systems