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 Hc and 1700 Oe for Hd were found to be in good agreement with theoretical predictions. The threshold rf field at Hc is 0.65 Oe. This threshold field for spin-wave instability gives a spin-wave linewidth (ΔHK) of 1.24 Oe. The susceptibility curve rises sharply at Hd, peaks in the vicinity of Hc, 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.