Current induced magnetization switching in permanent magnet biased CPP-GMR elements

摘要

It is well known that CPP-GMR is one of promising candidates for future high areal-density recording heads. Not only high MR ratio but also low noise is important to realize good S/N ratio. Control of current induced magnetization switching (CIMS) due to spin-transfer [1,2] is considered to be one of important issues for low noise. CIMS has been extensively examined especially for spin injection writing application. However, there seems to be no report for CIMS in actual CPP-GMR elements for head application. In this paper we report CIMS in CPP-GMR spin valve elements with longitudinal permanent magnet bias and present sense current density limit without CIMS.