Quantum discord surge heralds entanglement revival in an infinite spin chain
School of Physical Sciences, Jawaharlal Nehru University - New Delhi 110067, India
2 Harish-Chandra Research Institute - Chhatnag Road, Jhunsi, Allahabad 211019, India
Accepted: 17 April 2012
A measure of quantum correlation defined from an information-theoretic perspective, namely, quantum discord, is applied to study the time-evolved nonequilibrium state of the infinite anisotropic quantum XY spin chain in a transverse time-dependent field. In particular, we probe whether the collapse and revival of nearest-neighbor entanglement of the state seen with a varying initial applied field strength, at a fixed evolution time, may be predicted from the behavior of the quantum correlation measure. For this quantum many-body system, realizable with currently available technology, we find that the revival of entanglement of the evolved state occurs if there is an increase in quantum discord in the vicinity of entanglement collapse.
PACS: 03.67.-a – Quantum information / 75.10.Pq – Spin chain models / 75.10.Jm – Quantized spin models, including quantum spin frustration
© EPLA, 2012