First-principle study on the electronic structure and optical property of new diluted magnetic semiconductor (Y0.75Sr0.25) (Cu0.75Mn0.25)SO

In this research, we investigated the electronic structure and optical property of new diluted magnetic semiconductor (Y0.75Sr0.25) (Cu0.75Mn0.25)SO with decoupled charge and spin doping by first-principle calculation. We also compared (Y0.75Sr0.25) (Cu0.75Mn0.25)SO with pure YCuSO, and found that (Y0.75Sr0.25) (Cu0.75Mn0.25)SO is still a direct semiconductor with a band gap 1.20eV. The important difference from YCuSO is that the DOS of (Y0.75Sr0.25) (Cu0.75Mn0.25)SO presents asymmetry around fermi surface, leading to obvious spin order and ferror-magnetism due to the p-d hybridization through Mn 3d and S 3p. In case of the optical properties (including reflectivity coefficient, absorption coefficient, the imaginary part and real part of complex dielectric constant), the intensity of all peaks for both pure and doped YCuSO tends to zero above 15.5eV. However, the value of all the peaks for (Y0.75Sr0.25) (Cu0.75Mn0.25)SO reduces to some extent due to the Sr and Mn dopant. In addition, the position of all the peaks for (Y0.75Sr0.25) (Cu0.75Mn0.25)SO have a “red shift”, probably originating from the impurity states generated by the p-d hybridization through Mn 3d and S 3p. This will be beneficial for searching new 1111 phase DMS.