Electron paramagnetic resonance was used to investigate Mn impurity in Bi2Se3 topological insulator grown by the vertical Bridgman method. Mn in high-spin S = 5/2, Mn2+ configuration, was detected regardless of the conductivity type of the host material. This means that Mn2+(d5) energy level is located within the valence band, and Mn1+(d6) energy level is outside the energy gap of Bi2Se3. The electron paramagnetic resonance spectrum of Mn2+ in Bi2Se3 is characterized by the isotropic g-factor |g| = 1.91 and large axial parameter D = -4.20 GHz x h. This corresponds to the zero-field splitting of the Kramers doublets equal to 8.4 GHz x h and 16.8 GHz x h, respectively, which is comparable to the Zeeman splitting for the X-band. Mn in Bi2Se3 acts as an acceptor, effectively reducing native-high electron concentration, compensating selenium vacancies, and resulting in p-type conductivity.
@article{arxiv.1412.2012,
title = {Electron Paramagnetic Resonance of Mn in Bi$_2$Se$_3$ Topological Insulator},
author = {Agnieszka Wolos and Aneta Drabinska and Maria Kaminska and Andrzej Hruban and Stanislawa G. Strzelecka and Andrzej Materna and Miroslaw Piersa and Magdalena Romaniec and Ryszard Diduszko},
journal= {arXiv preprint arXiv:1412.2012},
year = {2014}
}