TY - JOUR
T1 - Magnetic properties of Dy nano-islands on graphene
AU - Anderson, Nathaniel A.
AU - Zhang, Qiang
AU - Hupalo, Myron
AU - Rosenberg, Richard A.
AU - Freeland, John W.
AU - Tringides, Michael C.
AU - Vaknin, David
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/8/1
Y1 - 2017/8/1
N2 - We have determined the magnetic properties of epitaxially grown Dy islands on graphene/SiC(0001) that are passivated by a gold film (deposited in the ultra-high vacuum growth chamber) for ex-situ X-ray magnetic circular dichroism (XMCD). Our sum-rule analysis of the Dy M4,5 XMCD spectra at low temperatures (T=15 K) as a function of magnetic field assuming Dy3+ (spin configuration 6H15/2) indicate that the projection of the magnetic moment along an applied magnetic field of 5 T is 3.5(3) μB. Temperature dependence of the magnetic moment (extracted from the M5 XMCD spectra) shows an onset of a change in magnetic moment at about 175 K in proximity of the transition from paramagnetic to helical magnetic structure at TH=179 K in bulk Dy. No feature at the vicinity of the ferromagnetic transition of hcp bulk Dy at Tc = 88 K is observed. However, below ∼130 K, the inverse magnetic moment (extracted from the XMCD) is linear in temperature as commonly expected from a paramagnetic system suggesting different behavior of Dy nano-island than bulk Dy.
AB - We have determined the magnetic properties of epitaxially grown Dy islands on graphene/SiC(0001) that are passivated by a gold film (deposited in the ultra-high vacuum growth chamber) for ex-situ X-ray magnetic circular dichroism (XMCD). Our sum-rule analysis of the Dy M4,5 XMCD spectra at low temperatures (T=15 K) as a function of magnetic field assuming Dy3+ (spin configuration 6H15/2) indicate that the projection of the magnetic moment along an applied magnetic field of 5 T is 3.5(3) μB. Temperature dependence of the magnetic moment (extracted from the M5 XMCD spectra) shows an onset of a change in magnetic moment at about 175 K in proximity of the transition from paramagnetic to helical magnetic structure at TH=179 K in bulk Dy. No feature at the vicinity of the ferromagnetic transition of hcp bulk Dy at Tc = 88 K is observed. However, below ∼130 K, the inverse magnetic moment (extracted from the XMCD) is linear in temperature as commonly expected from a paramagnetic system suggesting different behavior of Dy nano-island than bulk Dy.
KW - Dysprosium
KW - Nano-islands
KW - STM
KW - XMCD
UR - http://www.scopus.com/inward/record.url?scp=85017535584&partnerID=8YFLogxK
U2 - 10.1016/j.jmmm.2017.04.007
DO - 10.1016/j.jmmm.2017.04.007
M3 - Article
AN - SCOPUS:85017535584
SN - 0304-8853
VL - 435
SP - 212
EP - 216
JO - Journal of Magnetism and Magnetic Materials
JF - Journal of Magnetism and Magnetic Materials
ER -