论文标题
电子和晶体结构的厚度依赖性$ _2 $超薄膜：抑制协作莫特·佩尔斯过渡
Thickness dependence of electronic and crystal structures in VO$_2$ ultrathin films: suppression of the collaborative Mott-Peierls transition
论文作者
论文摘要
通过$ {in 〜Situ} $光发射光谱，我们研究了维度控制的vo $ _2 $胶片在Tio $ _2 $（001）底物上相干生长的电子和晶体结构的变化。在纳米结构的膜中，带有带状Peierls过渡的不稳定性与Mott Transition之间的平衡是作为厚度的函数控制的。与温度驱动的金属 - 绝缘子在vo $ _2 $厚膜中的特征光谱变化相关，厚度厚度降至1.5 nm（大致对应于[001]方向沿[001]方向的五个V原子），而VO $ _2 $胶片的薄膜却低于1.0 nm，而无需V-V v-v dimerization。这些结果表明，莫特不稳定性和带状般的peierls不稳定性之间的微妙平衡是通过维度的交叉效应和限制效应以几种纳米量表进行调节的，从而诱导了超薄vo $ _2 $膜的复杂电子相。
Through ${in~situ}$ photoemission spectroscopy, we investigated the change in the electronic and crystal structures of dimensionality-controlled VO$_2$ films coherently grown on TiO$_2$(001) substrates. In the nanostructured films, the balance between the instabilities of a bandlike Peierls transition and a Mott transition is controlled as a function of thickness. The characteristic spectral change associated with temperature-driven metal-insulator transition in VO$_2$ thick films holds down to 1.5 nm (roughly corresponding to five V atoms along the [001] direction), whereas VO$_2$ films of less than 1.0 nm exhibit insulating nature without V-V dimerization. These results suggest that the delicate balance between a Mott instability and a bandlike Peierls instability is modulated at a scale of a few nanometers by the dimensional crossover effects and confinement effects, which consequently induce the complicated electronic phase diagram of ultrathin VO$_2$ films.
