Surface Versus Bulk Dirac States Tuning in a Three-Dimensional Topological Dirac Semimetal

Madhab Neupane; Su-Yang Xu; Nasser Alidoust; Raman Sankar; Ilya Belopolski; Guang Bian; Daniel S. Sanchez; Chang Liu; Tay-Rong Chang; Horng-Tay Jeng; BaoKai Wang; Guoqing Chang; Hsin Lin; Arun Bansil; Fangcheng Chou; M. Zahid Hasan

doi:10.1103/physrevb.91.241114

arXiv · 1501.00697

Surface Versus Bulk Dirac States Tuning in a Three-Dimensional Topological Dirac Semimetal

Madhab Neupane·Su-Yang Xu·Nasser Alidoust·Raman Sankar·Ilya Belopolski·Guang Bian·Daniel S. Sanchez·Chang Liu·Tay-Rong Chang·Horng-Tay Jeng·BaoKai Wang·Guoqing Chang·Hsin Lin·Arun Bansil·Fangcheng Chou·M. Zahid Hasan

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Abstract

Recently, crystalline-symmetry-protected three-dimensional (3D) bulk Dirac semimetal phase has been experimentally identified in a stoichiometric high-mobility compound, Cd3As2. The Dirac state observed in Cd3As2 has been attributed to originate mostly from the bulk state while calculations show that the bulk and surface states overlap over the entire Dirac dispersion energy range. In this study, we unambiguously reveal doping induced evolution of the ground state of surface and bulk electron dynamics in a 3D Dirac semimetal. We develop a systematic technique to isolate the surface and bulk states in Cd3As2, by simultaneously utilizing angle-resolved photoemission spectroscopy (ARPES) and in-situ surface deposition. Our experimental results provide a method for tuning the chemical potential as well as to observe surface states degenerate with bulk states, which will be useful for future applications of 3D Dirac semimetal.

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Madhab Neupane, Su-Yang Xu, Nasser Alidoust, Raman Sankar, Ilya Belopolski, Guang Bian, Daniel S. Sanchez, Chang Liu, Tay-Rong Chang, Horng-Tay Jeng, BaoKai Wang, Guoqing Chang, Hsin Lin, Arun Bansil, Fangcheng Chou, M. Zahid Hasan. 2015-01-04. Surface Versus Bulk Dirac States Tuning in a Three-Dimensional Topological Dirac Semimetal. https://doi.org/10.1103/physrevb.91.241114

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