Spontaneous Emission from an Inverted Spin System

Abstract

This paper summarizes the results of calculations made in an attempt to explain the origin of the observed modulation effects in two-level maser experiments [1,2]. In a spontaneously oscillating spin system any transverse magnetization, which couples rf power out of the spin system, which is due to the presence of a transverse rf field, which is in turn induced by the transverse magnetization. Any consideration of the dynamics of the spin system or the build-up of the radiation field must consequently treat the two systems simultaneously. Our analysis uses a model first formulated by Bloembergen and Pound [3], except that our problem is inherently nonlinear [4] and we cannot make the simplifying assumption Mz = const, which linearizes the the equations of motion, and are forced to have rescourse to an IBM 704.