Growth and transport properties of topological insulator Bi2Se3 thin film on a ferromagnetic insulating substrate

• 来源期刊: 中国物理B（英文版）
• 关键词: topological insulator ferromagnetic insulator molecular beam epitaxy magnetotransport proper-ties
• 年，卷（期）: 2018,（7）
• 页码范围: 492-499
• 页数: 8页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/7/076801

摘要

Exchange coupling between topological insulator and ferromagnetic insulator through proximity effect is strongly attractive for both fundamental physics and technological applications. Here we report a comprehensive investigation on the growth behaviors of prototype topological insulator Bi2Se3 thin film on a single-crystalline LaCoO3 thin film on SrTiO3 substrate, which is a strain-induced ferromagnetic insulator. Different from the growth on other substrates, the Bi2Se3 films with highest quality on LaCoO3 favor a relatively low substrate temperature during growth. As a result, an inverse dependence of carrier mobility with the substrate temperature is found. Moreover, the magnetoresistance and coherence length of weak antilocalization also have a similar inverse dependence with the substrate temperature, as revealed by the magnetotransport measurements. Our experiments elucidate the special behaviors in Bi2Se3/LaCoO3 heterostructures, which provide a good platform for exploring related novel quantum phenomena, and are inspiring for device applications.