Open AccessPECULIAR OPTICAL PROPERTIES OF Co2MnGa ALLOYS
Author(s) -
J. Y. Rhee,
Y. V. Kudryavtsev,
K.W. Kim,
Y.P. Lee
Publication year - 2017
Publication title -
asean journal on science and technology for development
Language(s) - English
Resource type - Journals
eISSN - 2224-9028
pISSN - 0217-5460
DOI - 10.29037/ajstd.181
Subject(s) - alloy , optical conductivity , density functional theory , plane wave , condensed matter physics , ellipsometry , local density approximation , density of states , materials science , absorption spectroscopy , conductivity , chemistry , electronic structure , molecular physics , optics , physics , computational chemistry , thin film , metallurgy , nanotechnology
Co2MnGa alloy was prepared by the conventional arc-melting method. The optical conductivity (OC) spectrum of the alloy was measured by a rotating-analyzer spectroscopic ellipsometer. The OC spectrum was also calculated based on the electronic structure by using the full-potential linearized-augmented-plane-wave method within the local-spin-density approximation to the density-functional theory. The calculated OC spectrum does not agree well with the experimental one. Since the Co2MnGa alloy could be a strongly-correlated material, the so-called 'LDA+U' method was applied with U = 5.4 eV. The calculated OC spectrum using the 'LDA+U' method agrees very well with the experimental one. The inclusion of the onsite Coulomb potential during the self-consistent calculation significantly modifies the minorityspin Co and Mn 3d bands, resulting in a contraction of the energy gaps between states which are strongly involved in interband absorption peaks. PACS. 78.66.Bz 78.20.Bh
Accelerating Research
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom
Address
John Eccles HouseRobert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom