1307.6034 (Yichen Huang)

Scaling of quantum discord in spin models    [PDF]

Yichen Huang

We study the scaling of quantum discord (a measure of quantum correlation beyond entanglement) in spin models analytically and systematically. We find that the block scaling of quantum discord for any 2-local Hamiltonian at finite temperature satisfies an area law. We show that generically the two-site scaling of quantum discord is similar to that of correlation functions. At zero temperature it decays exponentially and polynomially in gapped and gapless (critical) systems, respectively; at finite temperature it decays exponentially in both gapped and gapless systems. We compute the two-site scaling of quantum discord in the XXZ chain, the XY chain (in a magnetic field), and the transverse field Ising chain at zero temperature.

View original: http://arxiv.org/abs/1307.6034