TY  - JOUR
AU  - Maryško, M.
AU  - Hejtmánek, J.
AU  - Laguta, V.
AU  - Sofer, Z.
AU  - Sedmidubský, D.
AU  - Šimek, P.
AU  - Veselý, M.
AU  - Mikulics, M.
AU  - Buchal, C.
AU  - Macková, A.
AU  - Malínský, P.
AU  - Wilhelm, R. A.
TI  - Ferromagnetic and paramagnetic magnetization of implanted GaN:Ho,Tb,Sm,Tm films
JO  - Journal of applied physics
VL  - 117
IS  - 17
SN  - 1089-7550
CY  - Melville, NY
PB  - American Inst. of Physics
M1  - FZJ-2015-02738
SP  - 17B907 
PY  - 2015
AB  - The SQUID magnetic measurements were performed on the GaN films prepared by metal-organic vapour phase epitaxy and implanted by Tb3+, Tm3+, Sm3+, and Ho3+ ions. The sapphire substrate was checked by the electron paramagnetic resonance method which showed a content of Cr3+ and Fe3+ impurities. The samples 5 × 5 mm2 were positioned in the classical straws and within an estimated accuracy of 10−6 emu, no ferromagnetic moment was detected in the temperature region of 2–300 K. The paramagnetic magnetization was studied for parallel and perpendicular orientation. In the case of GaN:Tb sample, at T = 2 K, a pronounced anisotropy with the easy axis perpendicular to the film was observed which can be explained by the lowest quasi-doublet state of the non-Kramers Tb3+ ion. The Weiss temperature deduced from the susceptibility data using the Curie-Weiss (C-W) law was found to depend substantially on the magnetic field.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000354984100230
DO  - DOI:10.1063/1.4916761
UR  - https://juser.fz-juelich.de/record/189601
ER  -