Ab initio calculations of the electronic and magnetic properties of Co2FeSi-Au interface

L. MAKINISTIAN; E. A. ALBANESI; B. NADGORNY; A. G. PETUKHOV

Buenos Aires, Argentina

Workshop; "At the Frontiers of Condensed Matter IV: Current trends and novel materials" (FCM2008); 2008

CONEA, UBA y Uni. Nac. de San Martín

<!-- /* Font Definitions */ @font-face {font-family:SimSun; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-alt:宋体; mso-font-charset:134; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 135135232 16 0 262145 0;} @font-face {font-family:"@SimSun"; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-charset:134; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 135135232 16 0 262145 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:SimSun;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> In this work, we first review the electronic and magnetic properties of the bulk Heusler alloy Co2FeSi, in order to establish a reference baseline for a computational study of its interface with gold. We perform calculations using two different structural models, and applying both ASA and FP-LMTO, and FP-LAPW approaches with and without the inclusion of a Coulomb-exchange interaction, confirming previous results found for the bulk Co2FeSi and moving on to explore the electronic and magnetic properties of the interface at issue. We found a change of sign of the spin polarization of both the density of states and the ballistic conductance at the Fermi energy, at the interface; suggesting the tunneling of minority electrons. We compare our results with the experimental data on point contact Andreev reflection of Co2FeSi-Au structures.