Various challenges in realizing spin-gapless semiconductivity in Ti2CoSi
Journal of Magnetism and Magnetic Materials
Spin-gapless semiconductors are recently discovered class of materials that behave as an insulator for one spin channel and as a zero-gap semiconductor for the opposite spin. Here, we show from first-principle calculations that one such material Ti2CoSi predicted to exhibit spin-gapless semiconductivity has an energetically close non-spin-polarized phase. In particular, we show that the regular Heusler phase of this material is non-magnetic, while the inverted Heusler phase is nearly spin-gapless semiconducting, with a very small energy difference of ≈0.1 eV per 16-atom cell, in favor of the regular Heusler structure. Moreover, we also show that a 100% spin polarization in inverted Heusler phase is detrimentally affected by the emergence of surface states in thin-film geometry. These results need to be taken into account for realistic implementations of this and similar materials in nano-device applications, which rely on highly spin-polarized current in thin-film geometry.
Department of Physics
Original Publication Date
DOI of published version
UNI ScholarWorks, Rod Library, University of Northern Iowa
O'Leary, Evan; Dahal, Bishnu; Kharel, Parashu; and Lukashev, Pavel, "Various challenges in realizing spin-gapless semiconductivity in Ti2CoSi" (2020). Faculty Publications. 238.