Interval Identification of FMR Parameters for Spin Reorientation Transition in (Ga,Mn)As

Abstract

In this work we report results of ferromagnetic resonance studies of a 6% 15 nm (Ga,Mn)As layer, deposited on (001)-oriented GaAs.The measurements were performed with in-plane oriented magnetic eld, in the temperature range between 5 K and 120 K. We observe a temperature induced reorientation of the eective where (1) is shape anisotropy, (2) ordinary uni- * corresponding author; e-mail: marek.gutowski@ifpan.edu.pl axial out-of-plane anisotropy, (3) uniaxial in-plane anisotropy, and (4) fourfold, in-plane anisotropy.Here polar angles θ and φ refer to the orientation of the magnetization vector, M , not to the orientation of an external eld H. Original experimental data, taken at xed frequency 9.378 GHz, are shown in Fig. 1, together with simulated spectra.The numerical values of three parameters: H eff = 4πM − H 2⊥ (where H 2⊥ ≡ 2K 2⊥ /M ), H 2∥ and H 4∥ were determined for each temperature separately. Outline of numerical procedureWe are using interval calculations not only for accurate simulations of FMR spectra when the values of all relevant parameters are known, but also to estimate (t) (1228)

Reliable uncertainties in indirect measurements

“…The combination of interval calculus with probability is tempting but certainly uneasy to satisfy. The papers in this area are appearing only recently 8,25,26,27,28 and still remain scarce. Our approach, as presented below, tries to follow this trend but seems more general and at the same time generally easier to follow.…”