title: Long-lived ultrafast spin precession in manganese alloys films with a large perpendicular magnetic anisotropy.
abstract: Spin precession with frequencies up to 280 GHz is observed in Mn(3-δ)Ga alloy films with a perpendicular magnetic anisotropy constant K(u)∼15  M erg/cm(3). The damping constant α, characterizing macroscopic spin relaxation and being a key factor in spin-transfer-torque systems, is not larger than 0.008 (0.015) for the δ=1.46 (0.88) film. Those are about one-tenth of α values for known materials with large K(u). First-principles calculations well describe both low α and large K(u) for these alloys.
authors.affiliation: WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan. mizukami@wpi-aimr.tohoku.ac.jp
authors.forename: S
authors.initials: S
authors.lastname: Mizukami
authors.forename: F
authors.initials: F
authors.lastname: Wu
authors.forename: A
authors.initials: A
authors.lastname: Sakuma
authors.forename: J
authors.initials: J
authors.lastname: Walowski
authors.forename: D
authors.initials: D
authors.lastname: Watanabe
authors.forename: T
authors.initials: T
authors.lastname: Kubota
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Naganuma
authors.forename: M
authors.initials: M
authors.lastname: Oogane
authors.forename: Y
authors.initials: Y
authors.lastname: Ando
authors.forename: T
authors.initials: T
authors.lastname: Miyazaki