Fast Flux Reversal in Laminated Nickel–Iron Thin Films

Abstract

THIS communication deals with fast flux reversal in 80–20 nickel–iron films laminated with silicon monoxide. The magnetization curves of such films were shown by Clow¹ to be characterized by very low coercive forces. The laminated film used in this measurement consisted of ten laminations of nickel–iron, each 200 Å thick, separated by silicon monoxide of about half the nickel–iron thickness. The silicon monoxide and nickel–iron layers were deposited alternately using a differential shutter. A control film was deposited at the same time but screened from the silicon monoxide, and therefore was essentially a solid film of nickel–iron 2000 Å thick. The films were 1 cm diameter spots evaporated on to glass substrates at 320° C in a pressure of about 1 × 10⁻⁵ mm mercury. The nickel–iron deposition rate was 25 Å/sec. The laminated films had an easy direction coercivity, H_c = 0.17 œrsteds, and an anisotropy field, H_K = 3.9 œrsteds, while the control films had H_c = 0.76 œrsteds and H_K = 3.4 œrsteds.