TY - JOUR
T1 - Magnetic phases in Ge-Fe thin films containing high Fe content
AU - Song, S. H.
AU - Jung, M. H.
AU - Lim, S. H.
PY - 2006/12/13
Y1 - 2006/12/13
N2 - Magnetic phases in evaporated thin films of Ge100-xFe x (x in at.%) alloys with x ≤ 36.6 and 51.8 are examined. At x ≤ 36.6, a single amorphous phase is formed. The magnetic phase at room temperature appears to be ferromagnetic, and it transforms into a spin-glass phase at 20K. The magnetic phases are more complicated at the higher Fe composition of x ≤ 51.8, which is mainly due to the presence of Fe precipitates in the amorphous matrix. An analysis based on the superparamagnetism indicates that the effective composition of the amorphous phase is estimated to be x ≤ 39.4, and this amorphous phase shows a similar magnetic behaviour to that observed in the x ≤ 36.6 sample with the exception of a slightly higher spin freezing temperature of 30K. Due to the Fe precipitates, an additional superparamagnetic behaviour is observed with a blocking temperature of 160K. Magnetization saturation in the spin-glass state occurs at a relatively small applied field, which indicates that the direct antiferromagnetic exchange coupling between Fe ions is weak.
AB - Magnetic phases in evaporated thin films of Ge100-xFe x (x in at.%) alloys with x ≤ 36.6 and 51.8 are examined. At x ≤ 36.6, a single amorphous phase is formed. The magnetic phase at room temperature appears to be ferromagnetic, and it transforms into a spin-glass phase at 20K. The magnetic phases are more complicated at the higher Fe composition of x ≤ 51.8, which is mainly due to the presence of Fe precipitates in the amorphous matrix. An analysis based on the superparamagnetism indicates that the effective composition of the amorphous phase is estimated to be x ≤ 39.4, and this amorphous phase shows a similar magnetic behaviour to that observed in the x ≤ 36.6 sample with the exception of a slightly higher spin freezing temperature of 30K. Due to the Fe precipitates, an additional superparamagnetic behaviour is observed with a blocking temperature of 160K. Magnetization saturation in the spin-glass state occurs at a relatively small applied field, which indicates that the direct antiferromagnetic exchange coupling between Fe ions is weak.
UR - http://www.scopus.com/inward/record.url?scp=33846106892&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33846106892&partnerID=8YFLogxK
U2 - 10.1088/0953-8984/18/49/018
DO - 10.1088/0953-8984/18/49/018
M3 - Article
AN - SCOPUS:33846106892
VL - 18
SP - 11263
EP - 11274
JO - Journal of physics. Condensed matter : an Institute of Physics journal
JF - Journal of physics. Condensed matter : an Institute of Physics journal
SN - 0953-8984
IS - 49
M1 - 018
ER -