氧化物分子束外延技术及其在关联材料电子态研究中的应用

氧化物分子束外延薄膜和异质结生长技术近年来迅速发展,人们已实现以单原子层的精度来精确生长多种复杂量子材料,有力地推动了铜氧化物高温超导电性、二维电子气、氧化物电子学和自旋电子学器件等领域的研究.文章介绍了氧化物分子束外延的技术关键,并以La1-xSrxMnO3薄膜为例,介绍了钙钛矿结构的氧化物薄膜生长和刻画.特别是文章作者通过建立超高真空下的原位样品传送系统,可把薄膜样品直接传送到角分辨光电子能谱仪中,实现了薄膜的原位电子结构测量.所测得的La1-xSrxMnO3的电子结构与能带计算结果较为相符.而此类立方结构的、不可解理材料的电子结构,过去往往是无法直接测量的.

Oxide molecular beam epitaxy and its applications in the study of electronic states of correlated materials

Oxide molecular beam epitaxy technique has been rapidly developed in the recent years.Oxide films and heterostrutures can be made with the precision of single atomic layer,which has helped facilitate the research of high temperature superconductivity,two dimensional electron gas,and oxide-based electronics and spintronics.Taking La1-xSrxMnO3 thin film as an example,we introduce the oxide molecular beam epitaxy and basic characterizations for a perovskite thin film.Moreover,we show that by combining oxide molecular beam epitaxy and angle resolved photoemission spectroscopy,in-situ electronic structure measurements become feasible for thin films.The measured electronic structure of La1-xSrxMnO3 thin film shows fairly good agreement with the band structure calculations,while previously the electronic structure of such uncleavable cubic-structured materials usually could not be obtained with photoemission spectroscopy.