Subthreshold Steady-State Absorption under Parallel Pumping

Abstract

If the rf and dc magnetic fields are parallel, the absorption coefficient μ″ at low power levels is theoretically expected (for YIG at room temperature, a frequency of 10 Gc/sec, and a dc field of 1 kOe) to be of the order of 2×10⁻⁴. We have calculated how the steady‐state absorption varies with dc and rf field strength below the instability threshold. Experiments on a high‐purity YIG single crystal are in reasonably good agreement with the theoretical expectations.