Long-Lived Ultrafast Spin Precession in Manganese Alloys Films with a Large Perpendicular Magnetic Anisotropy

S. Mizukami,* F. Wu, A. Sakuma, J. Walowski, D. Watanabe, T. Kubota, X. Zhang, H. Naganuma, M. Oogane, Y. Ando, and T. Miyazaki WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan Department of Applied Physics, Tohoku University, Sendai 980-8579, Japan I. Physikalisches Institut, Universittat Gottingen, 37077 Gottingen, Germany (Received 24 August 2010; published 16 March 2011)