The magnetic and electronic properties of boron-doped SrTiO3 have been studied by first-principles calculations. We found that the magnetic ground states of B-doped SrTiO3 strongly depended on the dopant-dopant separation distance. As the dopant–dopant distance varied, the magnetic ground states of B-doped SrTiO3 can have nonmagnetic, ferromagnetic or antiferromagnetic alignment. The structure with the smallest dopant-dopant separation exhibited the lowest total energy among all configurations considered and was characterized by dimer pairs due to strong attraction. Ferromagnetic coupling was observed to be stronger when the two adjacent B atoms aligned linearly along the B-Ti-B axis, which could be associated with their local bonding structures. Therefore, the symmetry of the local structure made an important contribution to the generation of a magnetic moment. Our study also demonstrated that the O-Ti-O unit was easier than the Ti-B-Ti unit to deform. The electronic properties of boron-doped SrTiO3 tended to show semiconducting or insulating features when the dopant–dopant distance was less than 5 Å, which changed to metallic properties when the dopant–dopant distance was beyond 5 Å. Our calculated results indicated that it is possible to manipulate the magnetism and band gap via different dopant–dopant separations.

中文翻译：

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调谐掺硼钛酸锶中的磁性

通过第一性原理计算研究了掺硼SrTiO3的磁性和电子性质。我们发现，B掺杂SrTiO3的磁性基态强烈依赖于掺杂剂-掺杂剂的分离距离。随着掺杂剂-掺杂剂距离的变化，掺B的SrTiO3的磁性基态可以具有非磁性，铁磁性或反铁磁性排列。在所有考虑的构型中，具有最小掺杂剂-掺杂剂间隔的结构显示出最低的总能量，并且由于强吸引而具有二聚体对。当两个相邻的B原子沿B-Ti-B轴线性排列时，观察到铁磁耦合更强，这可能与其局部键合结构有关。所以，局部结构的对称性对磁矩的产生做出了重要贡献。我们的研究还表明，O-Ti-O单元比Ti-B-Ti单元更容易变形。当掺杂剂-掺杂剂的距离小于5Å时，硼掺杂SrTiO3的电子性能趋于呈现半导体或绝缘特性，而当掺杂剂-掺杂剂的距离超过5Å时，其电子性能会转变为金属性能。我们的计算结果表明，可以通过不同的掺杂剂-掺杂剂分离来控制磁性和带隙。当掺杂物-掺杂物的距离超过5Å时，金属变成了金属性质。我们的计算结果表明，可以通过不同的掺杂剂-掺杂剂分离来控制磁性和带隙。当掺杂物-掺杂物的距离超过5Å时，金属变成了金属性质。我们的计算结果表明，可以通过不同的掺杂剂-掺杂剂分离来控制磁性和带隙。