1. Half-Metallic Ferromagnetism in Fe-doped Zn3P2 From First-Principles Calculations
G. JAI GANESH and S. MATHI JAYA Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam – , Tamil Nadu, India
Author’s
Poster Number : G - 128
ABSTRACT
CALCULATIONAL DETAILS
Electronic Charge Density Distribution Plane
The DFT as implemented in VASP along with PAW pseudo-potential is used for the calculations.
Metal atoms 3d and 4s, and P atom 3s and 3p states were included.
cutoff energy 350 eV and 14×14×11 k-point mesh is used.
The optimization of the undoped and doped structures were carried out.
For the doping studies a Fe atom is substituted for Zn in the unit cell with 40 atoms.
Spin-polarized calculations are performed using the spin
interpolation scheme proposed by Vosko et al (6).
Ferromagnetic stability is calculated from the total energy
difference (ΔE) of the unit cell between FM and NM configurations.
Using the first-principles calculations based on the density functional theory, we have studied the magnetism and electronic structure of Fe-doped Zn3P2. Our results show that the half-metallic ground state and ferromagnetic stability for small Fe concentrations. The structural stability of the doped material has been studied. A large value of the magnetic moment is obtained from our calculations and it suggests that it may be a useful material in semiconductor spintronics.
Zn3P2
Zn2.875Fe0.125P2
INTRODUCTION
Diluted Magnetic Semiconductors (DMS’s) are important materials
in the field of spintronics.
They exhibit promising applications in the areas of magneto-
transport, optical, electronic and photo-voltaic devices.
During the recent past years several transition metal doped III-V and II-VI wide band gap semiconductors have been synthesized and studied extensively using both experimental and theoretical techniques [1].
Examples: Cr doped GaN, AlN and ZnTe
Transition metals doped TiO2, In2O3, Mn-doped GaN and ZnO
Mn-doped (A = Cd, Zn; B = Si, Ge; C = P, As) chalcopyrite’s
However, the II-V compound semiconductors are not well studied !!!
RESULTS AND DISCUSSION
Electronic Band Structure of Pure Zn3P2
Zn2.875Fe0.125P2
II-V COMPOUND SEMICONDUCTORS
Stimulated XRD
II-V compounds have unusual transport and photo-voltaic properties.
Compared to other semiconductors, these compounds are studied less because
of its complex crystal structures and large number of atoms.
Zn3P2 is an earth abundant, low cost compound, polar, mixed ionic-covalent bond, p-type semiconducting material, easy to fabricate them as a thin-film with great potential as a photo-voltaic material.
There exists many works devoted to the preparation and investigation of Zn3P2 based thin-film photo-voltaic devices for solar energy application [2-4].
However, their electronic and magnetic properties are not explored !!!
Our Goal: To investigate the electronic structure and half-metallic
ferromagnetic properties of Fe-doped Zn3P2 .
Calculated parameters for pure and Fe doped Zn3P2
Parameters
Zn3P2
Zn2.875Fe0.125P2
Present
Exp.2,4,5
Lattice Parameters (Å) a
8.101
8.089
8.091 c
11.519
11.407
11.441
Formation Energy (eV)
-1.306
-1.530
-1.271
Band gap (eV)
0.450
1.490 -
ΔE (eV)
-0.369
CONCLUSIONS
In this work, we have studied the ferromagnetism of Zn3P2 induced by Fe doping using DFT calculations.
We found that the Fe atom doping can induce simultaneously magnetic and semiconducting properties and half-metallic ferromagnetism in Zn3P2.
Fe-doped Zn3P2 is more stable in the ferromagnetic phase with the
magnetic moment of Fe is μB.
Density of States
CRYSTALLINE STRUCTURE
Acknowledgments
Semiconducting
nature
One of the authors (G. Jaiganesh) wishes to thank the Council of Scientific and Industrial Research, New Delhi, India for the award
of Research Associateship (Grant No.: 9/532(0026)/2013 EMR-1).
References
1. Weimin and Irina Buyanova, “Computational Materials Design in Semiconductor Nano-spintronics” in Handbook of Spintronic Semiconductors, Singapore: Pan Stanford Publishing, 2010, pp.1-80.
2. Wan-Jian Yin and Yanfa Yan, J. Appl. Phys. 113, (1-5), (2013).
3. P. J. Lin-Chung, Phys. Stat. Sol. (b) 47, 33-39, (1971).
4. K. Sieranski, J. Szatkowski, and J. Misiewicz, Phys. Rev. B 50, No. 11, , (1994).
J.L.C. Daams, P. Villars and J. H. N. van Vucht, Atlas of Crystal Structure
Types for Intermetallic Phases, Materials Park, OH: ASM International, 1991, pp.3908. 6.
Primitive Tetragonal Lattice - P42/nmc (No.: 137) - 40 atoms (24 Zn and 16 P) unit cell.
There exist three different type of cation atom Zn (1), Zn (2), Zn (3) and they occupy 8g sites of the space group P42/nmc whereas the anion P(1), P(2), P(3) atoms occupy the 4c, 4d and 8f sites respectively.
Ferromagnetism
&
Half-metal