| (Ga,Mn)(As,Sb), a quaternary diluted magnetic semiconductor(DMS) has been researched in this paper, concluding the film growth, lattice structure and magnetic properties, etc.GaAs-based quaternary ferromagnetic semiconductor (Ga,Mn)(As,Sb) films with different Sb component have been successfully prepared by low temperature molecular-beam epitaxy(LT-MBE). High-resolution x-ray diffraction measurements show the high quality crystal lattice and the nominal Mn content has been estimated from the lattice constant. The calculation indicate that the lattice constant has a notable alteration with changing Sb content. Magnetic measurements demonstrate the same evolution of the Curie temperature TC and the effective Mn content xeff with increasing Sb content. The incorporation of low Sb content is of benefit to increasing xeff, thus, increasing TC. However, higher Sb content degrades the crystal quality, resulting in a decrease of xeff. Experimental results show that TC is proportional to the product of xeff and p1/3, which is consistent with the Zener Model. The exchange energy N0β is calculated to be-1.09eV which is similar to that of (Ga,Mn)As.The Raman spectra of (Ga,Mn)(As,Sb) have been studied in a quasi-backscattering geometry at room temperature by using457nm excitation of the Ar+laser. The incorporation of Sb has an important contribution in the peak-moving and the symmetry characterization of Raman peaks. The hole density has been calculated by fitting the experimental data using two Lorentzian oscillators and the spectral shape formula, and compared with the result of magnetic transport. It shows that for low Mn content of samples, two-apex fitting got close to magnetic transport results. However, with the increase of Mn and Sb content, the improvement of Raman peak symmetry will disable the bimodal fitting. Good sample for Raman peak symmetry, using the unimodal fitting method of spectral shape formula is close to magnetic transport of results are obtained. |
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