Recent discovery of bulk insulating topological insulator (TI) Bi2-xSbxTe3-ySey paved a pathway toward practical device application of TIs. For realizing TI-based devices, it is necessary to contact TIs with a metal. Since the band-bending at the interface dominates the character of devices, knowledge of TIs' work function is of essential importance. We have determined the compositional dependence of work function in Bi2-xSbxTe3-ySey by high-resolution photoemission spectroscopy. The obtained work-function values (4.95-5.20 eV) show a systematic variation with the composition, well tracking the energy shift of the surface chemical potential seen by angle-resolved photoemission spectroscopy. The present result serves as a useful guide for developing TI-based electronic devices.
@article{arxiv.1606.07933,
title = {Work function of bulk-insulating topological insulator Bi2-xSbxTe3-ySey},
author = {Daichi Takane and Seigo Souma and Takafumi Sato and Takashi Takahashi and Kouji Segawa and Yoichi Ando},
journal= {arXiv preprint arXiv:1606.07933},
year = {2016}
}