Anisotropy of infrared-active phonon modes in the monodomain state of tetragonal SrTiO3 (110)

Article

关键词: 2-DIMENSIONAL ELECTRON-GAS;    DIELECTRIC RESPONSE;    STRONTIUM-TITANATE;    DOMAIN-STRUCTURE;    ELLIPSOMETRY;    SURFACE;   

DOI  :  10.1103/PhysRevB.95.024105

来源: SCIE

【 摘 要 】

With infrared (IR) and terahertz (THz) ellipsometry we investigated the anisotropy of the IR-active phonon modes in SrTiO3 (110) single crystals in the tetragonal state below the so-called antiferrodistortive transition at T* = 105 K. In particular, we show that the anisotropy of the oscillator strength of the so-called R mode, which becomes weakly IR active below T*, is a valuable indicator of the orientation of the structural domains. Our results reveal that a monodomain state with the tetragonal axis (c axis) parallel to the [001] direction can be created by applying a moderate uniaxial stress of about 2.3 MPa along the [1-10] direction (with a simple mechanical clamp). The resulting splitting of the IR-active phonon modes is reported.

【 授权许可】

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