Tailoring Magnetic and Transport Anisotropies in Co100−x–Cux Thin Films through Obliquely Grown Nano-Sheets

Magnetochemistry

José Vergara¹  Cristina Favieres¹  Vicente Madurga¹ 

[1] Laboratory of Magnetism, Department of Science (Physics), Public University of Navarre (UPNA), Campus de Arrosadía, 31006 Pamplona, Spain;

关键词: magnetic thin films;    nano-morphology;    magnetic anisotropy;    transport properties;    structural relaxation;    activation energy spectra;   

DOI  :  10.3390/magnetochemistry8010004

来源: DOAJ

【 摘 要 】

The magnetic and transport properties of pulsed laser-deposited Co_100−x–Cu_x thin films were tailored through their nano-morphology and composition by controlling for the deposition geometry, namely normal or oblique deposition, and their Cu content. All films were composed of an amorphous Co matrix and a textured growth of Cu nanocrystals, whose presence and size d increased as x increased. For x = 50, all films were superparamagnetic, regardless of deposition geometry. The normally deposited films showed no in-plane magnetic anisotropy. On the contrary, controllable in-plane uniaxial magnetic anisotropy in both direction and magnitude was generated in the obliquely deposited films. The magnetic anisotropy field H_k remained constant for x = 0, 5 and 10, H_k ≈ 35 kAm⁻¹, and decreased to 28 and 26 kAm⁻¹ for x = 20 and 30, respectively. This anisotropy had a magnetostatic origin due to a tilted nano-sheet morphology. In the normally deposited films, the coercive field H_c increased when x increased, from 200 (x = 0) to 1100 Am⁻¹ (x = 30). In contrast, in obliquely deposited films, H_c decreased from 1500 (x = 0) to 100 Am⁻¹ (x = 30) as x increased. Activation energy spectra corresponding to structural relaxation phenomena in obliquely deposited films were obtained from transport property measurements. They revealed two peaks, which also depended on their nano-morphology and composition.

【 授权许可】

Unknown