【摘要】 采用第一性原理计算方法,对本征Mn₄Si₇以及P和As掺杂的Mn₄Si₇的电子结构和光学性质进行计算解析。计算结果表明本征Mn₄Si₇是带隙值为0.810 eV的间接带隙半导体材料,P掺杂Mn₄Si₇的带隙值增大为0.839 eV,As掺杂Mn₄Si₇的带隙值减小为0.752 eV。掺杂使得Mn₄Si₇的能带结构和态密度向低能方向移动,同时使得介电函数的实数部分在低能区明显增大,虚数部分几乎全部区域增加且8 eV以后趋向于零。此外掺杂还增加了高能区的消光系数、吸收系数、反射系数以及光电导率,明显改善了Mn₄Si₇的光学性质。更多还原

【Abstract】 The electronic structure and optical properties of intrinsic and P, As doped Mn₄Si₇ were calculated with the fisrt-principles calculation method. The result shows that the intrinsic Mn₄Si₇ is an indirect semiconductor material with a gap of 0.810 eV, the P doped Mn₄Si₇ band gap increases to 0.839 eV, and the As doped Mn₄Si₇ band gap decreases to 0.752 eV. Doping causes a shift to the low energy region, and causes an increase of the real part of dielectric function notably in the low energy region and an increase of the imaginary part in almost all region, imaginary part decreases to zero after 8 eV. Besides, doping obviously increases the extinction coefficient, absorption coefficient reflection coefficient and photoconductivity in the high energy region, and improves the optical properties of the Mn₄Si₇.更多还原