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Entanglement spectrum, critical exponents, and order parameters in quantum spin chains
G De Chiara1, L Lepori, M Lewenstein
1Departament de Física, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain.
Physical Review Letters
|February 2, 2013
Summary
The entanglement spectrum
Area of Science:
- Quantum physics
- Condensed matter theory
Background:
- Quantum phase transitions
- Entanglement spectrum
- Quantum spin chains
Purpose of the Study:
- Investigate entanglement spectrum near criticality
- Identify critical points
- Explore scaling behavior
Main Methods:
- Finite size scaling
- Reduced density matrix eigenvalues
- Schmidt gap analysis
Main Results:
- Schmidt gap signals critical points
- Universal scaling with critical exponents
- Schmidt gap as a local order parameter
Conclusions:
- The Schmidt gap is a universal indicator of quantum phase transitions
- Scaling behavior of the Schmidt gap provides critical exponents
- Local order parameter identified
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