Magneto optical properties of β [110] and ω [100] titanium nanowires

Abstract

In this article, the electric, magnetic and optical properties of β phase of [110] and ω phase of [100] titanium nanowires are investigated using the density functional theory approach, the full potential augmented plane wave plus local orbital method (FLAPW+lo) and the generalized gradient approximation (GGA). Infinite and free standing periodic nanowires were considered with super cell approach and the optimized structure and bond length were calculated. Optimized radii of TiNWs reduced ∼10% from the bulk to the nanophase in the β phase while it was around ∼5% for the ω phase. Band structures, density of states and magnetic properties of these configurations were also calculated. The interesting parameter of the spin polarization of the electrons at the Fermi level was 0.30μB/atom for β and 0.14μB/atom for the ωTiNWs. These structures showed a particular magnetic moment in comparison with the related bulk phases, and titanium nanochains. The value of magnetic moment of 0.511μB/atom occurred in ωTiNWs while the bulk phase was nonmagnetic. Additionally, optical properties of TiNWs-like dielectric function, energy loss function and optical conductivity and absorption of nanowires were calculated. These properties changed noticeably from the bulk to nanowire phase, especially in the static dielectric function and optical absorption. Peaks in the imaginary part of the dielectric function were communicated in order to allow the interband transitions in the band structure. Moreover, the nanowire absorption spectra showed a number of distinct peaks, which could be attributed to the surface plasmon resonance.