Electronic structure and magnetic properties of diluted magnetic semiconductor K and Mn co-doped BaCd2As2 from first-principles calculations

2014 ◽  
Vol 28 (14) ◽  
pp. 1450111 ◽  
Author(s):  
L. Hua ◽  
Q. L. Zhu
Keyword(s):  
Magnetic Properties ◽  
Electronic Structure ◽  
Density Functional ◽  
Diluted Magnetic Semiconductor ◽  
Magnetic Semiconductor ◽  
Antiferromagnetic Coupling ◽  
Generalized Gradient ◽  
Diluted Magnetic ◽  
Mn Doped ◽  
Co Doped

In this paper, we have investigated the electronic structure and magnetic properties of K and Mn co-doped BaCd 2 As 2 using density functional theory within the generalized gradient approximation ( GGA ) + U schemes. Calculations show that the ground state magnetic structure of Mn -doped BaCd 2 As 2 is antiferromagnetic while K and Mn co-doped BaCd 2 As 2 is ferromagnetic. Electronic structures indicate that the superexchange mechanism leads to the antiferromagnetic coupling between Mn atoms in Mn -doped BaCd 2 As 2 while the hole-mediated Zener's p–d exchange mechanism leads to the ferromagnetic coupling between Mn atoms in K and Mn co-doped BaCd 2 As 2.

scholarly journals Magnetic Properties of Co doped ZnS Diluted Magnetic Semiconductor

2013 ◽  
Vol 430 ◽  
pp. 012076 ◽  
Author(s):  
Qingteng Hou ◽  
Kai Chen ◽  
Hongguang Zhang ◽  
Yongtao Li ◽  
Hao Liu ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Diluted Magnetic Semiconductor ◽  
Magnetic Semiconductor ◽  
Diluted Magnetic ◽  
Co Doped

An Electronic Structure Study of Mn Doped ZnO Diluted Magnetic Semiconductor Using X-Ray Absorption and Photoemission Techniques

2009 ◽  
Vol 155 ◽  
pp. 163-172
Author(s):  
R.K. Singhal ◽  
M.S. Dhawan ◽  
S.K. Gaur ◽  
Elisa Saitovitch
Keyword(s):  
Magnetic Properties ◽  
Electronic Structure ◽  
Diluted Magnetic Semiconductor ◽  
Room Temperature Ferromagnetism ◽  
Magnetic Semiconductor ◽  
Transition Metal Ions ◽  
X Ray ◽  
Two Samples ◽  
Diluted Magnetic ◽  
X Ray Absorption

ZnO semiconductor doped with a few per cent of some transition metal ions can exhibit above room temperature ferromagnetism, transforming it into a very promising candidate for future spin-electronic applications. In the present article we have compared the electronic structure of two polycrystalline ZnMnO pellets doped with diluted Mn concentration (2% and 4%), carefully characterized by SQUID and XRD, including Rietveld refinement. The characterization measurements established that the samples have the ZnO lattice with ZnS type Wurtzite hexagonal symmetry and no detectable impurities. The samples exhibit distinctly different magnetic properties. The 2% sample displayed a clear FM ordering at 300 K while the 4% sample did not show any ordering down to 5K. The electronic structure of these two samples has been investigated using Mn L23 x-ray absorption spectroscopy, Zn 2p and 3p, Mn 3p and O 1s x-ray photoemission spectroscopy. Our aim was to find out how the changes in the electronic structure can correlate to the observed magnetic properties in such diluted magnetic semiconductor materials. The results show that most of the Mn ions of the ferromagnetic sample are in the divalent state. For the higher Mn percent nonmagnetic sample, a larger contribution of higher oxidation Mn states are dominant and the oxygen content also increases. The two factors can be correlated to the suppressed ferromagnetism, though it is hard to pinpoint that which of these two weighs more in the suppression mechanism.

Tunable electronic structure and magnetic properties of Mn–NM (NM = B, C, N and S) co-doped monolayer WSe2

2019 ◽  
Vol 33 (35) ◽  
pp. 1950446
Author(s):  
Wenlong Lai ◽  
Lixin Wang ◽  
Yukai An
Keyword(s):  
Magnetic Properties ◽  
Electronic Structure ◽  
Magnetic Materials ◽  
Spin Polarization ◽  
Density Functional ◽  
Chemical Potential ◽  
Spin Exchange ◽  
Potential Range ◽  
Mn Doped ◽  
Co Doped

Searching two-dimensional (2D) magnetic materials with high spin polarization is important for the development and application of next-generation spintronic devices. Here, based on spin-polarized density functional theory calculations, the stability, electronic structure and magnetic properties of Mn-doped and Mn–NM (NM = B, C, N and S) co-doped monolayer WSe2 are investigated in detail. The results indicate that the Mn–S co-doped MoSe2 configuration has the lowest formation energy in the whole chemical potential range and easily spontaneously forms under thermodynamic equilibrium conditions. Obviously, the Mn-doped WSe2 configuration exhibits magnetic half-metallicity characters with a completely spin polarization at the Femi level [Formula: see text], which can be attributed to that the electrons partially occupy the bonding states consisting of Mn [Formula: see text] states at the [Formula: see text]. For the Mn–C and Mn–S co-doped configurations, the Mn [Formula: see text] and [Formula: see text] orbitals strongly hybridize with the C or S spin-up [Formula: see text] orbital at the [Formula: see text], which induces strong spin exchange splitting and eventually gives rise to the magnetic semiconductor character. However, the Mn–B and Mn–N co-doped configurations exhibit completely symmetrical spin-up and spin-down channel of [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] states due to the effective charge compensation between Mn and B or N atoms. These studies provide a new class of 2D magnetic materials for future spintronics devices.

Sign in / Sign up

Export Citation Format

Share Document