Nature of magnetic coupling between Mn ions in As-grown Ga1-xMnxAs studied by X-ray magnetic circular dichroism.
The magnetic properties of as-grown Ga1-xMnxAs have been investigated by the systematic measurements of temperature and magnetic field dependent soft x-ray magnetic circular dichroism (XMCD). The intrinsic XMCD intensity at high temperatures obeys the Curie-Weiss law, but a residual spin magnetic moment appears already around 100 K, significantly above the Curie temperature (T_{C}), suggesting that short-range ferromagnetic correlations are developed above T_{C}. The present results also suggest that the antiferromagnetic interaction between the substitutional and interstitial Mn (Mn_{int}) ions exists and that the amount of the Mn_{int} affects T_{C}.
Takeda
Y
Y
Japan Atomic Energy Agency, Synchrotron Radiation Research Center SPring-8, Sayo, Hyogo 679-5148, Japan. ytakeda@spring8.or.jp
Kobayashi
M
M
Okane
T
T
Ohkochi
T
T
Okamoto
J
J
Saitoh
Y
Y
Kobayashi
K
K
Yamagami
H
H
Fujimori
A
A
Tanaka
A
A
Okabayashi
J
J
Oshima
M
M
Ohya
S
S
Hai
P N
PN
Tanaka
M
M