高分子辅助沉积法制备Sm x Nd1- x NiO3 外延薄膜

Sm x Nd1- x NiO3 Thin-Films with Tunable Metal–Insulator Transition Grown by Polymer-Assisted Deposition

摘要:

采用高分子辅助沉积法制备掺杂不同钐（Sm）含量的Sm_xNd_1-xNiO₃外延薄膜（钐掺杂量x=0.5，0.55，0.6）。X射线衍射（特征θ-2θ扫描、摇摆曲线和φ-scan）和扫描电子显微镜的测试结果表明，制备的薄膜结晶性和外延性良好，与衬底的（001）取向保持一致。电阻率-温度曲线表明制备的外延薄膜均表现出金属绝缘体转变现象。随着Sm掺杂量的提高，金属绝缘体转变温度逐渐升高；当x=0.55时，外延薄膜的转变温度在室温附近。并且高分子辅助沉积法可以简单有效地制备热致变色外延薄膜。

Abstract:

The epitaxial Sm_xNd_1-xNiO₃ (x=0.5, 0.55, 0.6, SNNO) thin films with (001)-oriented single-crystal LaAlO₃ substrates were fabricated by a chemical solution deposition technique, namely polymer-assisted deposition (PAD) under the ambient oxygen annealing. X-ray diffraction θ-2θ scan, rocking curve measurement, φ-scan and scanning electron microscopy were used to study the SNNO characteristics. The results reveal the good crystallinity and heteroepitaxy of these SNNO films. Temperature dependence of the resistivity indicates that all the films show a clear Mott metal-insulator transition (MIT) and the transition temperature (T_MI) shifts to higher temperature with the increase of Sm content. The epitaxial Sm_0.55Nd_0.45NiO₃ thin films exhibit MIT near room temperature. The successful growth of high quality SNNO films with room temperature transition by economic and facile PAD method shows great potential in practical application of nickelate.