Electronic and magnetic properties of MnSnAs2

Nanodevice Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea
physica status solidi (b) (Impact Factor: 1.61). 05/2004; 241(7):1462 - 1465. DOI: 10.1002/pssb.200304641

ABSTRACT We have synthesized MnSnAs2 single crystals using the vertical temperature gradient solidification method. The crystal structure of MnSnAs2 is chalcopyrites, which are “genealogically” related to the more familiar tetrahedrally-coordinated zinc-blende materials, with lattice constants of a = 5.794 Å, c = 11.365 Å. Using the experimentally determined lattice constants and crystal structure, we carried out first principles electronic structure calculations, using the full-potential linearized augmented plane wave (FLAPW) method in the local density approximation (LDA). The lowest total energies were observed for the AFM state, indicating that AFM ordering in the system is energetically favored at 0 K. We find that MnSnAs2 is metallic in the electronic calculation. Interestingly, MnSnAs2 exhibited ferromagnetism with TC = 328 K. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

  • [Show abstract] [Hide abstract]
    ABSTRACT: ZnSnAs2 thin film doped with ∼4% Mn was grown on (001) InP substrates by all elemental solid source molecular beam epitaxy using the previously determined optimum substrate temperature of 300°C and Zn:Sn:As4 beam equivalent pressure ratio of 24:1:52. In this work, we have employed slower growth rate by halving the beam equivalent pressures of Zn, Sn and As4 we have used in our earlier reports, while maintaining the same beam equivalent pressure ratio. From the high-resolution X-ray diffraction (HRXRD) data, the computed lattice constant a is 5.867Å, which is in very good agreement with the reported lattice constant value of the bulk ZnSnAs2 chalcopyrite, suggesting that lowering the growth rate leads to a transition to a more chalcopyrite structure. The average composition ratio of Zn:Sn:As:Mn according to electron probe micro-analysis (EPMA) studies is 1:0.826:2.42:0.076. Hysteretic M–H curves were obtained at 5, 100, 300 and 320K using a superconducting quantum interference device (SQUID) magnetometer. The Curie temperature was estimated to be ∼330K from the zero-field cooled temperature dependence of magnetization. The possible origin of this above-room-temperature ferromagnetism is discussed.
    Journal of Crystal Growth 01/2009; 311(3):929-932. DOI:10.1016/j.jcrysgro.2008.09.110 · 1.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report the molecular beam epitaxy (MBE) growth of lightly Mn-doped Zn–Sn–As-based compounds on (001) InP substrates. Our XRD measurements showed peaks assignable to sphalerite-type ZnSnAs2:Mn, a supposition further supported by our EPMA and TEM analyses. The optimum substrate temperature TS resulting into the most stoichiometric ZnSnAs2 epitaxial films was first determined by growing undoped ZnSnAs2 at different TS of 265, 280, 300, and 320°C. The sample grown at TS=300°C showed the best stoichiometry according to our EPMA composition studies. We then prepared lightly Mn-doped ZnSnAs2 at this optimum substrate temperature of 300°C. Room temperature SQUID measurements revealed paramagnetic response with weak ferromagnetism as evident from the slightly S-shape M–H curve superimposed on a linearly increasing magnetization with increasing field.
    Journal of Crystal Growth 04/2007; 301:656-661. DOI:10.1016/j.jcrysgro.2006.12.015 · 1.69 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The ab initio calculations of electronic and magnetic properties of chalcopyrites (II = Be, Zn, Cd; IV = Si, Ge; V = P, As) doped with 3d metals are presented within the scope of interest for semiconductor spintronics. Different concentrations of V, Cr, Mn, Fe, and Co atoms replacing II–II, II–IV, and IV–IV group sites are checked and the most stable configurations for each case are determined. The appearance of magnetic moments and the ferromagnetic state upon doping is analyzed. It is revealed that for all materials incorporation of Cr or Mn atoms leads to the appearance of magnetic moments, but only substitution of II group atoms yields a stable configuration with a ferromagnetic state. High spin polarization is obtained for Zn–IV–P2 and Zn–IV–As2 compounds whose lattice parameters are close to that of silicon and germanium (or GaAs), respectively. Moreover, the substitution of Be by Cr atoms in Be–IV–As2 semiconductors (having a lattice parameter close to silicon) transforms them into half-metals stable in the ferromagnetic state. Recommendations upon the further applicability of investigated materials for spintronics are proposed.
    physica status solidi (b) 02/2014; 251(5). DOI:10.1002/pssb.201350305 · 1.61 Impact Factor

Full-text (2 Sources)

Available from
Jun 4, 2014