Theory of Spin Resonance and Relaxation in an Interacting Spin System

抄録

In an interacting spin system, spin resonance and relaxation are studied. From the von Neumann equation, a generalized Bloch equation is derived directly by making use of the method of orthogonal operators expansion, which has been developed in a previous paper. The linearization conditions, i. e., (spin energy) <<kT and the spin I=1⁄2, which were required in earlier theories, are eliminated. The theory is valid at all temperatures and for arbitrary spin. At high temperatures, the result coincides with Argyres and Kelley’s one for a system of independent spins except for the definition of relaxation times. The theory is also applicable to the rigid lattice. The steady-state magnetization is studied.