TY - JOUR
T1 - Entanglement spectrum, critical exponents, and order parameters in quantum spin chains
AU - De Chiara, G.
AU - Lepori, L.
AU - Lewenstein, M.
AU - Sanpera, A.
PY - 2012/12/5
Y1 - 2012/12/5
N2 - We investigate the entanglement spectrum near criticality in finite quantum spin chains. Using finite size scaling we show that when approaching a quantum phase transition, the Schmidt gap, i.e., the difference between the two largest eigenvalues of the reduced density matrix λ1, λ2, signals the critical point and scales with universal critical exponents related to the relevant operators of the corresponding perturbed conformal field theory describing the critical point. Such scaling behavior allows us to identify explicitly the Schmidt gap as a local order parameter. © 2012 American Physical Society.
AB - We investigate the entanglement spectrum near criticality in finite quantum spin chains. Using finite size scaling we show that when approaching a quantum phase transition, the Schmidt gap, i.e., the difference between the two largest eigenvalues of the reduced density matrix λ1, λ2, signals the critical point and scales with universal critical exponents related to the relevant operators of the corresponding perturbed conformal field theory describing the critical point. Such scaling behavior allows us to identify explicitly the Schmidt gap as a local order parameter. © 2012 American Physical Society.
U2 - https://doi.org/10.1103/PhysRevLett.109.237208
DO - https://doi.org/10.1103/PhysRevLett.109.237208
M3 - Article
VL - 109
M1 - 237208
ER -