INRS-EMT, 1650 Lionel-Boulet, C. P. 1020, Varennes Québec, J3X 1S2, Canada.
Département de Physique, Université de Montréal, CP. 6128 Succ. Centre-ville, Montréal, Québec H3C 3J7, Canada.
Sci Rep. 2017 Jan 18;7:40915. doi: 10.1038/srep40915.
Samarium nickelate (SmNiO) thin films were successfully synthesized on LaAlO and SrTiO substrates using pulsed-laser deposition. The Mott metal-insulator (MI) transition of the thin films is sensitive to epitaxial strain and strain relaxation. Once the strain changes from compressive to tensile, the transition temperature of the SmNiO samples shifts to slightly higher values. The optical conductivity reveals the strong dependence of the Drude spectral weight on the strain relaxation. Actually, compressive strain broadens the bandwidth. In contrast, tensile strain causes the effective number of free carriers to reduce which is consistent with the d-band narrowing.
采用脉冲激光沉积法在 LaAlO 和 SrTiO 衬底上成功合成了钐镍酸盐（SmNiO）薄膜。薄膜的莫特金属-绝缘体（MI）转变对外延应变和应变弛豫敏感。一旦应变从压缩变为拉伸，SmNiO 样品的转变温度就会略微升高。光学电导率揭示了 Drude 谱权重对应变弛豫的强烈依赖。实际上，压缩应变会拓宽带宽。相比之下，拉伸应变会导致有效自由载流子数量减少，这与 d 带变窄一致。
