Effect of transition-metal overlayers on the perpendicular magnetism of MBE-grown, ultra-thin Co films

Journal Article · Sat May 15 00:00:00 EDT 1993 · Journal of Applied Physics; (United States)

DOI:https://doi.org/10.1063/1.352694· OSTI ID:6678861

Engel, B N; Wiedmann, M H; Van Leeuwen, R A; Falco, C M ^[1]

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1. Physics Department and Optical Sciences Center, University of Arizona, Tucson, Arizona 85721 (United States)

We have used [ital in] [ital situ] polar Kerr ellipticity measurements to study the perpendicular magnetic behavior of MBE-grown Pd/Co/TM sandwich structures, where TM is the nonmagnetic transition metal overlayer Pd, Cu, or Ag. These structures are epitaxially deposited on thick Pd (111) buffer layers grown on Co-seeded GaAs (110) substrates. Hysteresis curves were measured [ital in] [ital situ] for systematically varied Co and TM layer thicknesses 2 A[le][ital t][sub Co][le]10 A and 0 A[le][ital t][sub TM][le]200 A. We observed perpendicular loops with a coercive field of [ital H][sub [ital c]][le]200 Oe for the uncovered Co films for [ital t][sub Co][le]6 A, becoming in-plane above this thickness. However, subsequent deposition of just one atomic layer ([approx]2 A) of any of the TM over the Co resulted in strongly perpendicular, square hysteresis curves with [ital H][sub [ital c]][ge]700 Oe for all films in the Co thickness range studied. Deposition of TM overlayers causes nonmonotonic behavior in [ital H][sub [ital c]] as a function of coverage. We find a peak in [ital H][sub [ital c]] at a TM coverage of [ital t][sub TM][similar to]1.5 A for all materials, with a subsequent monotonic increase above [ital t][sub TM][approx]4 A to a limiting value by [ital t][sub TM][approx]100 A. The peak is most pronounced for Cu, where [ital H][sub [ital c]] changes by more than 200%.

• DOE Contract Number: FG02-87ER45297
• OSTI ID: 6678861
• Journal Information: Journal of Applied Physics; (United States), Vol. 73:10; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COBALT
MAGNETIC PROPERTIES
COPPER
KERR EFFECT
LAYERS
MOLECULAR BEAM EPITAXY
PALLADIUM
SILVER
THIN FILMS
DIELECTRIC PROPERTIES
ELECTRICAL PROPERTIES
ELEMENTS
EPITAXY
FILMS
METALS
PHYSICAL PROPERTIES
PLATINUM METALS
TRANSITION ELEMENTS
360104* - Metals & Alloys- Physical Properties