Entanglement of Low-Energy Excitations in Conformal Field Theory

Journal Article · Fri May 20 00:00:00 EDT 2011 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.106.201601· OSTI ID:21538343

Alcaraz, Francisco Castilho ^[1]; Ibanez Berganza, Miguel; Sierra, German ^[2]

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1. Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Caixa Postal 369, Sao Carlos, SP (Brazil)
2. Instituto de Fisica Teorica UAM/CSIC, Universidad Autonoma de Madrid, Cantoblanco 28049, Madrid (Spain)

In a quantum critical chain, the scaling regime of the energy and momentum of the ground state and low-lying excitations are described by conformal field theory (CFT). The same holds true for the von Neumann and Renyi entropies of the ground state, which display a universal logarithmic behavior depending on the central charge. In this Letter we generalize this result to those excited states of the chain that correspond to primary fields in CFT. It is shown that the nth Renyi entropy is related to a 2n-point correlator of primary fields. We verify this statement for the critical XX and XXZ chains. This result uncovers a new link between quantum information theory and CFT.

• OSTI ID: 21538343
• Journal Information: Physical Review Letters, Vol. 106, Issue 20; Other Information: DOI: 10.1103/PhysRevLett.106.201601; (c) 2011 American Institute of Physics; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CONFORMAL INVARIANCE
ENTROPY
EXCITATION
EXCITED STATES
QUANTUM ENTANGLEMENT
QUANTUM FIELD THEORY
QUANTUM INFORMATION
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
FIELD THEORIES
INFORMATION
INVARIANCE PRINCIPLES
PHYSICAL PROPERTIES
THERMODYNAMIC PROPERTIES