Ultrafast optically induced ferromagnetic/anti-ferromagnetic phase transition in GdTiO3 from first principles
Ultrafast optically induced ferromagnetic/anti-ferromagnetic phase transition in GdTiO3 from first principles
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DOI：
10.1038/s41535-018-0086-3
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发表时间：
2018-03-12
影响因子：
5.7
通讯作者：
Benedek, Nicole A.
中科院分区：
文献类型：
--
作者：
Khalsa, Guru;Benedek, Nicole A.
外延生长和化学取代一直是功能材料设计的主要手段。这些静态技术已经在通过调整微妙的结构扭曲来控制复杂氧化物的性质方面取得了巨大的成功。最近，一种基于用强中红外光激发红外活性声子的方法，通过与拉曼声子的特殊非线性耦合，为结构的动态控制创造了机会。我们使用第一性原理技术表明，这种方法可以动态地诱导磁相变从铁磁基态到一个隐藏的反铁磁相的稀土钛酸盐GdTiO 3的现实的实验参数。我们表明，Jahn-Teller失真，Gd位移和红外声子运动的组合主导这个相变的八面体旋转的影响很小，与传统的智慧。
Epitaxial strain and chemical substitution have been the workhorses of functional materials design. These static techniques have shown immense success in controlling properties in complex oxides through the tuning of subtle structural distortions. Recently, an approach based on the excitation of an infrared active phonon with intense midinfrared light has created an opportunity for dynamical control of structure through special nonlinear coupling to Raman phonons. We use first-principles techniques to show that this approach can dynamically induce a magnetic phase transition from the ferromagnetic ground state to a hidden antiferromagnetic phase in the rare earth titanate GdTiO3 for realistic experimental parameters. We show that a combination of a Jahn-Teller distortion, Gd displacement, and infrared phonon motion dominate this phase transition with little effect from the octahedral rotations, contrary to conventional wisdom.