Experimental and theoretical studies of Ti2MnGa

Abstract

We synthesized and investigated Ti2MnGa Heusler compound, which was not studied experimentally before and which was previously predicted by ab-initio calculations to be a spin-gapless semiconductor. Our measurements of magnetic susceptibility and magnetization clearly show that this compound does not exhibit magnetic ordering. It agrees well with our constrained band structure calculations which give lowest total energy for non-magnetic unit cell in a simple Heusler structure of Cu2MnAl-type. Resistivity vs. temperature dependence is typical for disordered Heusler alloy, whereas magnetoresistivity is very small, of about 0.15% at 9 T. Photoemission spectra of Mn 2p states also do not show signs of magnetic ordering. We studied the quality of the sample using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and X-ray Fluorescence (XRF) as well as Time of Flight Secondary Ion Mass Spectroscopy (TOF-SIMS) techniques.