Structural, magnetic and magneto-transport properties of Pt-alloyed MnBi thin films

Authors

• Parashu Kharel, University of Nebraska-LincolnFollow
• Ralph Skomski, University of Nebraska-LincolnFollow
• Roger D. Kirby, University of Nebraska-LincolnFollow
• David J. Sellmyer, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2010

Comments

Published in JOURNAL OF APPLIED PHYSICS 107, 09E303 (2010). Copyright © 2010 American Institute of Physics. Used by permission.

Abstract

The structural, magnetic and magneto-transport properties of highly c-axis oriented Mn_55−xPt_xBi₄₅ (x=0, 1.5, 3, and 4.5) thin films have been investigated. The coercivity of the Pt-alloyed thin films increases and the saturation magnetization decreases as the Pt concentration increases. The anisotropy field H_o increases as a function of Pt concentration, too but the coercivity increases more rapidly than the anisotropy field. This indicates an enhanced domain-wall pinning, caused by increased interstitial disorder due to the occupancy of regular Mn sites by Pt. The same mechanism explains the reduced magnetization. All samples exhibit a large extraordinary Hall effect with anomalous Hall coefficient about an order of magnitude larger than the ordinary Hall coefficient.