A Theory of Microwave Masers in Strong Pumping Field

概要

論文の詳細を見る
Maser action due to a mixing between unperturbed spin states, which is produced by a strong coherent pumping field at an angular frequency ω, is investigated by using rate equations of a spin deosity matrix referred to a rotating coordinate system. The relaxation of each state, which was introduced usually by phenomenological considerations, is obtained from an interaction Hamiltonian of the spin moments with local fields. The induced oscillating fields at 2ω±ω_8 and ω_8, which are proportional to a small signal field at a frequency ω_8, have the possibility of power emission (or absorption) by choosing suitably the pumping field. The components at 2ω±ω_8 are responsible for a frequency mixing between ω and ω±ω_8 occuring in the rotating coordinates. The emitted (or absorbed) line shape is not a simple Lorentzian in the case of the spin moment 1×h and considered to be a quantume affect in the three level scheme. The freqoencies of the emitted (or absorbed) fields are expected to be shifted by varying the magnitude, or the frequency of the pumping field, or the static magnetic field.
社団法人日本物理学会の論文
1964-11-05