论文标题
ktao的分子束外延$ _3 $
Molecular Beam Epitaxy of KTaO$_3$
论文作者
论文摘要
应变工程是一种强大的手段，可调节初期铁电的极性，结构和电子不稳定性。 KTAO3几乎是极性的不稳定性，并且在电子掺杂的样品中显示出各向异性的超导性。在这里，我们证明了通过分子束外延的高质量KTAO3薄膜的生长。 tantalum均由传统积液细胞中包含的TA2O5的TAO2通量以及电子束加热的tantalum源提供。与Tao $ _2 $（或tantalum）分子梁同时提供钾和氧气和氧气（10 \％O3 + 90 \％O2）的组合，以生长KTAO $ _3 $胶片。 Laue Fringes表明薄膜具有突然的膜/底物界面。横截面扫描透射电子显微镜未显示任何扩展的缺陷，并确认膜与底物具有原子界面。原子力显微镜在生长膜的表面揭示了原子步骤。相互的空间映射表明，如果足够薄的胶片相连，则与Srtio $ _3 $（001）和GDSCO $ _3 $（110）基板相连。
Strain-engineering is a powerful means to tune the polar, structural, and electronic instabilities of incipient ferroelectrics. KTaO3 is near a polar instability and shows anisotropic superconductivity in electron-doped samples. Here, we demonstrate growth of high quality KTaO3 thin films by molecular-beam epitaxy. Tantalum was provided by both a suboxide source emanating a TaO2 flux from Ta2O5 contained in a conventional effusion cell as well as an electron-beam-heated tantalum source. Excess potassium and a combination of ozone and oxygen (10 \% O3 + 90 \% O2) were simultaneously supplied with the TaO$_2$ (or tantalum) molecular beams to grow the KTaO$_3$ films. Laue fringes suggest that the films are smooth with an abrupt film/substrate interface. Cross-sectional scanning transmission electron microscopy does not show any extended defects and confirms that the films have an atomically abrupt interface with the substrate. Atomic force microscopy reveals atomic steps at the surface of the grown films. Reciprocal space mapping demonstrates that the films, when sufficiently thin, are coherently strained to the SrTiO$_3$ (001) and GdScO$_3$ (110) substrates.
