@article{10902/21949,
year = {2012},
url = {http://hdl.handle.net/10902/21949},
abstract = {This paper reports an experimental and theoretical investigation on the electronic structure of bismuth selenide (Bi2Se3) up to 9 GPa. The optical gap of Bi2Se3 increases from 0.17 eV at ambient pressure to 0.45 eV at 8 GPa. The quenching of the Burstein-Moss effect in degenerate samples and the shift of the free-carrier plasma frequency to lower energies reveal a quick decrease of the bulk three-dimensional (3D) electron concentration under pressure. On increasing pressure the behavior of Hall electron concentration and mobility depends on the sample thickness, consistently with a gradual transition from mainly 3D transport at ambient pressure to mainly two-dimensional (2D) transport at high pressure. Two-carrier transport equations confirm the trapping of high-mobility 3D electrons, an effect that can be related to a shallow-to-deep transformation of donor levels, associated with a change in the ordering of the conduction band minima. The high apparent areal density and low electron mobility of 2D electrons are not compatible with their expected properties in a Dirac cone. Measured transport parameters at high pressure are most probably affected by the presence of holes, either in an accumulation surface layer or as minority carriers in the bulk.},
organization = {This work has been done under financial support from Spanish MICINN under Grants No. MAT2008-06873-C02-
02, No. MAT2007-66129, No. MAT2010-21270-C04-03/04, No. CSD2007-00045, and Prometeo No.GV2011/035.},
publisher = {American Physical Society},
publisher = {Physical review. B, 2012, 85, 195139},
title = {Trapping of three-dimensional electrons and transition to two-dimensional transport in the three-dimensional topological insulator Bi2Se3 under high pressure},
author = {Segura, A. and Panchal, V. and Sánchez-Royo, J. F. and Marín-Borras, V. and Muñoz-Sanjosé, V. and Rodríguez-Hernández, P. and Muñoz, A. and Pérez-González, E. and Manjón, F. J. and González Gómez, Jesús Antonio},
}