- Zhang, Chaofan;
- Liu, Zhongkai;
- Chen, Zhuoyu;
- Xie, Yanwu;
- He, Ruihua;
- Tang, Shujie;
- He, Junfeng;
- Li, Wei;
- Jia, Tao;
- Rebec, Slavko N;
- Ma, Eric Yue;
- Yan, Hao;
- Hashimoto, Makoto;
- Lu, Donghui;
- Mo, Sung-Kwan;
- Hikita, Yasuyuki;
- Moore, Robert G;
- Hwang, Harold Y;
- Lee, Dunghai;
- Shen, Zhixun
The observation of replica bands in single-unit-cell FeSe on SrTiO3 (STO)(001) by angle-resolved photoemission spectroscopy (ARPES) has led to the conjecture that the coupling between FeSe electrons and the STO phonons are responsible for the enhancement of Tc over other FeSe-based superconductors. However the recent observation of a similar superconducting gap in single-unit-cell FeSe/STO(110) raised the question of whether a similar mechanism applies. Here we report the ARPES study of the electronic structure of FeSe/STO(110). Similar to the results in FeSe/STO(001), clear replica bands are observed. We also present a comparative study of STO(001) and STO(110) bare surfaces, and observe similar replica bands separated by approximately the same energy, indicating this coupling is a generic feature of the STO surfaces and interfaces. Our findings suggest that the large superconducting gaps observed in FeSe films grown on different STO surface terminations are likely enhanced by a common mechanism.