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Updated: May 18, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Optimal correlations in many-body quantum systems
1CNR-MATIS-IMM and Dipartimento di Fisica e Astronomia, Università di Catania, C/O ed. 10, viale A. Doria 6, I-95125 Catania, Italy.
Physical Review Letters
|September 26, 2012
Summary
Quantum measurements reveal information-correlation links in many-body spin chains. Optimal correlation extraction strategies depend on the quantum phase and interactions.
Area of Science:
- Quantum physics
- Condensed matter physics
- Quantum information theory
Background:
- Information and correlations are fundamentally linked in quantum systems via measurement.
- Understanding this relationship is crucial for advancing quantum metrology and condensed matter physics.
Purpose of the Study:
- To explore the relationship between information and correlations in a many-body quantum system.
- To investigate how positive-operator-valued measurements affect correlations.
Main Methods:
- Studied a one-dimensional array of interacting two-level systems (spin chain) at zero temperature.
- Adopted an information-theory perspective on correlations.
- Analyzed correlations after local positive-operator-valued measurements.
Main Results:
- Demonstrated that the amount of correlations changes based on the type of measurement performed.
- Showcased a dependency of optimal correlation extraction strategies on the quantum phase of the system.
- Highlighted a complex interplay between local interactions and quantum coherence.
Conclusions:
- The study provides insights into the fundamental connection between information and correlations in quantum many-body systems.
- Findings are relevant for developing advanced quantum measurement techniques and understanding quantum phase transitions.
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