Parallel Pumping in Narrow Linewidth Planar Mn–ZnY

Abstract

Parallel pump measurements were made on Mn‐substituted single‐crystal ZnY at room temperature and 17.2 kMc/sec. The experimentally determined values of 1500 Oe for H_c and 1700 Oe for H_d were found to be in good agreement with theoretical predictions. The threshold rf field at H_c is 0.65 Oe. This threshold field for spin‐wave instability gives a spin‐wave linewidth (ΔH_K) of 1.24 Oe. The susceptibility curve rises sharply at H_d, peaks in the vicinity of H_c, and then falls off slowly at lower values of dc field. The ferrimagnetic resonance linewidth and dc magnetization were studied as a function of increasing Mn substituent at room temperature. The resonance linewidth decreases with increasing Mn substitution. A minimum of 3.8 Oe at 9.0 kMc/sec is observed in crystals with approximately 4 to 5 wt % Mn. The magnetization decreases linearly with increasing Mn substituent.