Reduction of Transition Layer Thickness Showing Incoherent Switching Behavior in Single CoCrPt–SiO $_{2}$ Perpendicular Media

Magnetic switching behavior and activation volume (V act ) for CoCrPt-SiO 2 single layer media on two intermediate layer (IL) types of conventional Ru 1 /Ru 2 (IL1) and RuCr/Ru 2 (IL2) are investigated. Ru 1 and Ru 2 indicate the Ru layer deposited at low and high pressure of Ar, respectively. Replacement of Ru 1 with RuCr improves both crystallographic c-axis orientation (Deltathetas 50 ) of mag ). Both IL exhibit a similar trend in angular dependence of remanent coercivity (H cr ) but minimum value of H cr 45deg /H cr 0deg is observed at t mag = 15 nm for IL1 and 9 nm for IL2. The use of IL2 significantly reduces incoherent switching behavior at thinner t mag . Values of V act for both IL decrease with increasing t mag but IL2 provides considerably higher V act than IL1. In the media with IL2, higher H c and more coherent switching behavior at thinner t mag can be understood by contributions of narrower Deltathetas 50 , thinner transition layer thickness showing incoherent switching behavior, and higher V act .