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

Brad N. Engel, Michael H. Wiedmann, Robert A. Van Leeuwen, Charles M Falco

Research output: Contribution to journalArticle

35 Citations (Scopus)

Abstract

We have used in 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 in situ for systematically varied Co and TM layer thicknesses 2 Å≤t Co≤10 Å and 0 Å≤tTM≤200 Å. We observed perpendicular loops with a coercive field of Hc≤200 Oe for the uncovered Co films for tCo≤6 Å, becoming in-plane above this thickness. However, subsequent deposition of just one atomic layer (≊2 Å) of any of the TM over the Co resulted in strongly perpendicular, square hysteresis curves with Hc≥700 Oe for all films in the Co thickness range studied. Deposition of TM overlayers causes nonmonotonic behavior in Hc as a function of coverage. We find a peak in Hc at a TM coverage of tTM∼1.5 Å for all materials, with a subsequent monotonic increase above tTM≊4 Å to a limiting value by tTM≊100 Å. The peak is most pronounced for Cu, where Hc changes by more than 200%.

Original languageEnglish (US)
Pages (from-to)6192-6194
Number of pages3
JournalJournal of Applied Physics
Volume73
Issue number10
DOIs
StatePublished - 1993

Fingerprint

transition metals
hysteresis
sandwich structures
ellipticity
curves
buffers
causes

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Effect of transition-metal overlayers on the perpendicular magnetism of MBE-grown, ultra-thin Co films. / Engel, Brad N.; Wiedmann, Michael H.; Van Leeuwen, Robert A.; Falco, Charles M.

In: Journal of Applied Physics, Vol. 73, No. 10, 1993, p. 6192-6194.

Research output: Contribution to journalArticle

Engel, Brad N. ; Wiedmann, Michael H. ; Van Leeuwen, Robert A. ; Falco, Charles M. / Effect of transition-metal overlayers on the perpendicular magnetism of MBE-grown, ultra-thin Co films. In: Journal of Applied Physics. 1993 ; Vol. 73, No. 10. pp. 6192-6194.
@article{aaf0f08f93d34e349f486542d3d603e9,
title = "Effect of transition-metal overlayers on the perpendicular magnetism of MBE-grown, ultra-thin Co films",
abstract = "We have used in 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 in situ for systematically varied Co and TM layer thicknesses 2 {\AA}≤t Co≤10 {\AA} and 0 {\AA}≤tTM≤200 {\AA}. We observed perpendicular loops with a coercive field of Hc≤200 Oe for the uncovered Co films for tCo≤6 {\AA}, becoming in-plane above this thickness. However, subsequent deposition of just one atomic layer (≊2 {\AA}) of any of the TM over the Co resulted in strongly perpendicular, square hysteresis curves with Hc≥700 Oe for all films in the Co thickness range studied. Deposition of TM overlayers causes nonmonotonic behavior in Hc as a function of coverage. We find a peak in Hc at a TM coverage of tTM∼1.5 {\AA} for all materials, with a subsequent monotonic increase above tTM≊4 {\AA} to a limiting value by tTM≊100 {\AA}. The peak is most pronounced for Cu, where Hc changes by more than 200{\%}.",
author = "Engel, {Brad N.} and Wiedmann, {Michael H.} and {Van Leeuwen}, {Robert A.} and Falco, {Charles M}",
year = "1993",
doi = "10.1063/1.352694",
language = "English (US)",
volume = "73",
pages = "6192--6194",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics Publising LLC",
number = "10",

}

TY - JOUR

T1 - Effect of transition-metal overlayers on the perpendicular magnetism of MBE-grown, ultra-thin Co films

AU - Engel, Brad N.

AU - Wiedmann, Michael H.

AU - Van Leeuwen, Robert A.

AU - Falco, Charles M

PY - 1993

Y1 - 1993

N2 - We have used in 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 in situ for systematically varied Co and TM layer thicknesses 2 Å≤t Co≤10 Å and 0 Å≤tTM≤200 Å. We observed perpendicular loops with a coercive field of Hc≤200 Oe for the uncovered Co films for tCo≤6 Å, becoming in-plane above this thickness. However, subsequent deposition of just one atomic layer (≊2 Å) of any of the TM over the Co resulted in strongly perpendicular, square hysteresis curves with Hc≥700 Oe for all films in the Co thickness range studied. Deposition of TM overlayers causes nonmonotonic behavior in Hc as a function of coverage. We find a peak in Hc at a TM coverage of tTM∼1.5 Å for all materials, with a subsequent monotonic increase above tTM≊4 Å to a limiting value by tTM≊100 Å. The peak is most pronounced for Cu, where Hc changes by more than 200%.

AB - We have used in 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 in situ for systematically varied Co and TM layer thicknesses 2 Å≤t Co≤10 Å and 0 Å≤tTM≤200 Å. We observed perpendicular loops with a coercive field of Hc≤200 Oe for the uncovered Co films for tCo≤6 Å, becoming in-plane above this thickness. However, subsequent deposition of just one atomic layer (≊2 Å) of any of the TM over the Co resulted in strongly perpendicular, square hysteresis curves with Hc≥700 Oe for all films in the Co thickness range studied. Deposition of TM overlayers causes nonmonotonic behavior in Hc as a function of coverage. We find a peak in Hc at a TM coverage of tTM∼1.5 Å for all materials, with a subsequent monotonic increase above tTM≊4 Å to a limiting value by tTM≊100 Å. The peak is most pronounced for Cu, where Hc changes by more than 200%.

UR - http://www.scopus.com/inward/record.url?scp=0346249060&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0346249060&partnerID=8YFLogxK

U2 - 10.1063/1.352694

DO - 10.1063/1.352694

M3 - Article

AN - SCOPUS:0346249060

VL - 73

SP - 6192

EP - 6194

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

IS - 10

ER -