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Laser angle-resolved photoemission as a probe of initial state kz dispersion, final-state band gaps, and spin texture of Dirac states in the Bi2 Te3 topological insulator

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Original languageEnglish
Article number155144
Number of pages7
JournalPhysical Review B
Issue number15
Publication statusPublished - 27 Oct 2016
Publication typeA1 Journal article-refereed


We have obtained angle-resolved photoemission spectroscopy (ARPES) spectra from single crystals of the topological insulator material Bi2Te3 using a tunable laser spectrometer. The spectra were collected for 11 different photon energies ranging from 5.57 to 6.70 eV for incident light polarized linearly along two different in-plane directions. Parallel first-principles, fully relativistic computations of photointensities were carried out using the experimental geometry within the framework of the one-step model of photoemission. A reasonable overall accord between theory and experiment is used to gain insight into how properties of the initial- and final-state band structures as well as those of the topological surface states and their spin textures are reflected in the laser-ARPES spectra. Our analysis reveals that laser-ARPES is sensitive to both the initial-state kz dispersion and the presence of delicate gaps in the final-state electronic spectrum.

Publication forum classification

Field of science, Statistics Finland