Work

Systematic study of the spin stiffness dependence on phosphorus alloying in the ferromagnetic semiconductor (Ga,Mn)As

Year: 2015

Type: article

Abstract: We study the dependence of the spin stiffness constant on the phosphorus concentration in the ferromagnetic semiconductor (Ga,Mn)(As,P) with the aim of determining whether alloying with phosphorus is detrimental, neutral, or advantageous to the spin stiffness. Time-resolved magneto-optical experiments are carried out in thin epilayers. Laser pulses excite two perpendicular standing spin wave modes, which are exchange related. We show that the first mode is spatially uniform across the layer corresponding to a k≈0 wavevector. From the two frequencies and k-vector spacings we obtain the spin stiffness constant for different phosphorus concentrations using weak surface pinning conditions. The mode assessment is checked by comparison to the spin stiffness obtained from domain pattern analysis for samples with out-of-plane magnetization. The spin stiffness is found to exhibit little variation with phosphorus concentration in contradiction with ab-initio predictions.

Source: Applied Physics Letters

DOI: 10.1063/1.4917423

Authors: S. Shihab, H. Riahi, L. Thevenard, H. J. von Bardeleben, A. Lemaître, C. Gourdon

Institutions: Centre National de la Recherche Scientifique, Institut des NanoSciences de Paris, Université Pierre-et-Marie-Curie, University of Carthage

Language: English

Topic: Magnetic properties of thin films

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: bronze

Funders: Agence Nationale de la Recherche, Université Pierre et Marie Curie

Awards: G1538510618, G4093613618, G5205370647, Magnetization manipulation in ferromagnetic GaMnAs, Spin wave generation by surface acoustic waves in ferromagnetic thin films