Browsing by Author "Hsieh, H. H."

Now showing 1 - 3 of 3

Ferromagnetic GeMn thin film prepared by ion implantation and ion beam induced epitaxial crystallization annealing
(2012-06-11)
Chen, C. H.
;
Niu, H.
;
Yan, D. C.
;
Hsieh, H. H.
;
Lee, C. P.
Ferromagnetic GeMn was prepared by Mn implantation followed by ion beam-induced epitaxial crystallization annealing. The damage caused by Mn implantation was repaired by subsequent helium ion irradiation. Various structural analyses were performed and Mn ions were found to incorporate uniformly into the Ge lattice without the formation of any secondary phases. The remnant magnetic moment exhibited room temperature ferromagnetism. Anomalous Hall effect and field dependent magnetization were measured at the same time at room temperature indicating spin polarized free carrier transport. Additional measurement using x-ray magnetic circular dichroism also revealed that the carriers were spin-polarized. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729752]
Local structure and magnetic properties of ferromagnetic GaMnAs made by helium ion induced epitaxial crystallization annealing
(2014-08-15)
Chen, C. H.
;
Niu, H.
;
Yan, D. C.
;
Hsieh, H. H.
;
Huang, R. T.
In this study we show GaMnAs preparation by Mn implantation in GaAs followed by helium ion beam induced epitaxial crystallization annealing. The characteristics of the Mn-implanted layer were investigated by X-ray diffraction, and transmission electron microscopy. The magnetic nature of the Mn-implanted layer was investigated with a superconducting quantum interference device. Structure analysis showed that Mn ions were incorporated substitutionally into the GaAs lattice without the formation of any detectable secondary phases. The remanent magnetic moment exhibited room temperature ferromagnetism. Additional measurement using X-ray magnetic circular dichroism also revealed that the carriers were spin polarized. (C) 2014 Elsevier B.V. All rights reserved.
Local structure and magnetic properties of ferromagnetic GaMnAs made by helium ion induced epitaxial crystallization annealing
(2014-08-15)
Chen, C. H.
;
Niu, H.
;
Yan, D. C.
;
Hsieh, H. H.
;
Huang, R. T.
In this study we show GaMnAs preparation by Mn implantation in GaAs followed by helium ion beam induced epitaxial crystallization annealing. The characteristics of the Mn-implanted layer were investigated by X-ray diffraction, and transmission electron microscopy. The magnetic nature of the Mn-implanted layer was investigated with a superconducting quantum interference device. Structure analysis showed that Mn ions were incorporated substitutionally into the GaAs lattice without the formation of any detectable secondary phases. The remanent magnetic moment exhibited room temperature ferromagnetism. Additional measurement using X-ray magnetic circular dichroism also revealed that the carriers were spin polarized. (C) 2014 Elsevier B.V. All rights reserved.