Dynamics of entangled states of nuclear spins in solids

摘要

We investigated dynamics of entangled states on the basis of multiple-quantum (MQ) NMR methods. A time evolution of MQ coherences of nuclear spins coupled by the dipole-dipole interactions (DDI) in solids is simply connected with dynamics of quantum entangled states. We studied analytically dynamics of the entangled states for two- and three-spin systems. In this case dynamics of the quantum entanglement is uniquely determined by the time evolution of MQ coherences of the second order. The real part of the density matrix describing MQ dynamics in solids is responsible for MQ coherences of the zeroth order while its imaginary part is responsible for the second order. Thus, one can conclude that dynamics of the entanglement is connected with transitions from the real part of the density matrix to the imaginary one and vice versa.