期刊
ACS APPLIED MATERIALS & INTERFACES
卷 13, 期 19, 页码 23153-23160出版社
AMER CHEMICAL SOC
DOI: 10.1021/acsami.1c03168
关键词
topological insulator; spin-charge conversion; terahertz emission; surface hybridization; transition-metal oxide
资金
- National Research Foundation of Korea (NRF) - Government of Korea (MSIP) [2018R1A2A1A05023214, 2021M3H4A1A03052566]
- Ministry of Science & ICT (MSIT), Republic of Korea [GIST-04] Funding Source: Korea Institute of Science & Technology Information (KISTI), National Science & Technology Information Service (NTIS)
- National Research Foundation of Korea [2021M3H4A1A03052566, 2018R1A2A1A05023214] Funding Source: Korea Institute of Science & Technology Information (KISTI), National Science & Technology Information Service (NTIS)
Researchers induced dehybridization of ultrathin topological insulator films by breaking inversion symmetry between surfaces, leading to enhanced spin-charge conversion efficiency. By growing the film on an oxygen-deficient transition-metal oxide, they observed up to a 2.4 times increase in SCC efficiency through this method.
Owing to their remarkable spin-charge conversion (SCC) efficiency, topological insulators (TIs) are the most attractive candidates for spin-orbit torque generators. The simple method of enhancing SCC efficiency is to reduce the thickness of TI films to minimize the trivial bulk contribution. However, when the thickness reaches the ultrathin regime, the SCC efficiency decreases owing to intersurface hybridization. To overcome these contrary effects, we induced dehybridization of the ultrathin TI film by breaking the inversion symmetry between surfaces. For the TI film grown on an oxygen-deficient transition-metal oxide, the unbonded transition-metal d-orbitals affected only the bottom surface, resulting in asymmetric surface band structures. Spintronic terahertz emission spectroscopy, an emerging tool for investigating the SCC characteristics, revealed that the resulting SCC efficiency in symmetry-broken ultrathin Bi2Se3 was enhanced by up to similar to 2.4 times.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据