title: Effective reduction of critical current for current-induced magnetization switching by a Ru layer insertion in an exchange-biased spin valve.
abstract: Recently, it has been predicted that a spin-polarized electrical current perpendicular to plane directly flowing through a magnetic element can induce magnetization switching through spin-momentum transfer. In this Letter, the first observation of current-induced magnetization switching (CIMS) in exchange-biased spin valves (ESPVs) at room temperature is reported. The ESPVs show the CIMS behavior under a sweeping dc current with a very high critical current density. It is demonstrated that a thin ruthenium (Ru) layer inserted between a free layer and a top electrode effectively reduces the critical current densities for the CIMS. An "inverse" CIMS behavior is also observed when the thickness of the free layer increases.
authors.affiliation: Department of Materials Science, Graduate School of Engineering, Tohoku University, and CREST, Japan Science and Technology Agency, Sendai 980-8579, Japan. elejyong@hotmail.com
authors.forename: Y
authors.initials: Y
authors.lastname: Jiang
authors.forename: S
authors.initials: S
authors.lastname: Abe
authors.forename: T
authors.initials: T
authors.lastname: Ochiai
authors.forename: T
authors.initials: T
authors.lastname: Nozaki
authors.forename: A
authors.initials: A
authors.lastname: Hirohata
authors.forename: N
authors.initials: N
authors.lastname: Tezuka
authors.forename: K
authors.initials: K
authors.lastname: Inomata