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Phys. Rev. Lett. 75, 330–333 (1995)

[Issue 2 – July 1995 ]

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Suppression of Biquadratic Coupling in Fe /Cr(001) Superlattices below the Néel Transition of Cr

Eric E. Fullerton, K. T. Riggs, C. H. Sowers, and S. D. Bader

Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439

A. Berger

Department of Physics and Institute of Surface and Interface Science, University of California at Irvine, Irvine, California 92717

The Néel temperature ( T_N) of Cr in sputtered, epitaxial Fe /Cr(001) superlattices is identified via transport and magnetic anomalies. The onset of the antiferromagnetism is at a thickness t_Cr of 42 Å. The bulk value of T_N is approached asymptotically as t_Cr increases and is characterized by a three-dimensional shift exponent. Most strikingly, the biquadratic interlayer magnetic coupling (90° orientation of adjacent Fe layers), observed in the thick Cr regime, is suppressed below T_N. These results are attributed to finite-size effects and spin frustration near rough Fe-Cr interfaces.

©1995 The American Physical Society

URL: http://publish.aps.org/abstract/PRL/v75/p330
PACS: 75.70.Fr, 73.50.Jt, 75.30.Kz, 75.50.Rr

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