Fe Grain Grown on BiTeI Resolved by Scanning Tunneling Microscopy

• Main Authors: Wei-An Hsieh, 謝偉安
• Other Authors: Minn-Tsong Lin
• Format: Others
• Language: en_US
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/42244764574626274566

碩士 === 國立臺灣大學 === 物理研究所 === 104 === BiTeI, a Rashba semiconductor, contains signi cantly strong Rashba spin-splitting not only in the bulk energy band but also in the surface one. The fact that electrons with opposite spin direction have independent band structure is promising and helpful for spintronic device design in the future. For practical concern in device fabrication, we choose a widely-used magnetic material, iron, to explore its growth on the surface of BiTel. In this thesis, we investigate the surface properties of pristine BiTeI rst. We cleaved bulk BiTeI, and then used scanning tunneling microscopy (STM) to observe the cross section for studying its surface properties and defects. We also used scanning tunneling spectroscopy (STS) to probe its electronic band structure. The results con rmed that BiTeI exhibits two distinct surface terminations, Te-termination and I-termination, and were in agreement with the published literatures. Then we present iron adatoms grown on BiTeI by thermal evaporation. STM topographies showed that growth modes of two terminations were di erent, and STS data showed band shifts on both terminations. We think that the band shift from electronic properties changed after hybridization with iron atoms.