On the description of relaxation processes in nuclear magnetic resonance

昭二 市村

胥建卫, 陈起辉

We investigate the dynamics of the entanglement and quantum discord of two qubits in liquid state homonuclear nuclear magnetic resonance. Applying a phenomenological description for nuclear magnetic resonance under a relaxation process, and taking a group of typical parameters of nuclear magnetic resonance, we show that when a zero initial state experiences a relaxation process, its entanglement disappears completely after a sequence of so-called sudden deaths and revivals, while the quantum discord retains remarkable values after a sequence of oscillations. That is to say, the quantum discord is more robust than entanglement.

W. Apel, Yu. A. Bychkov

Jianwei Xu, Qihui Chen

We investigate the dynamics of the entanglement and quantum discord of two qubits in liquid state homonuclear nuclear magnetic resonance. Applying a phenomenological description for nuclear magnetic resonance under a relaxation process, and taking a group of typical parameters of nuclear magnetic resonance, we show that when a zero initial state experiences a relaxation process, its entanglement disappears completely after a sequence of so-called sudden deaths and revivals, while the quantum discord retains remarkable values after a sequence of oscillations. That is to say, the quantum discord is more robust than entanglement.

Luke Edwards, Dmitry Savostyanov, Zenawi Teklay Welderufael +2 more

Nuclear magnetic resonance spectroscopy is one of the few remaining areas of physical chemistry for which polynomially scaling quantum mechanical simulation methods have not so far been available. In this communication we adapt the restricted state space approximation to protein NMR spectroscopy and illustrate its performance by simulating common 2D and 3D liquid state NMR experiments (including accurate description of relaxation processes using Bloch-Redfield-Wangsness theory) on isotopically enriched human ubiquitin - a protein containing over a thousand nuclear spins forming an irregular polycyclic three-dimensional coupling lattice. The algorithm uses careful tailoring of the density operator space to only include nuclear spin states that are populated to a significant extent. The reduced state space is generated by analysing spin connectivity and decoherence properties: rapidly relaxing states as well as correlations between topologically remote spins are dropped from the basis set.

R. H. Terwiel, Paweł O. Mazur