Adatom defect induced spin polarization of asymmetric structures

The spin polarization of carbon nanomaterials is crucial to design spintronic devices. In this paper, the first-principles is used to study the electronic properties of two defect asymmetric structures, Cap-(9, 0)-Def [6, 6] and Cap-(9, 0)-Def [5, 6]. We found that the ground state of Cap-(9, 0)-Def [6, 6] is sextet and the ground state of Cap-(9, 0)-Def [5, 6] is quartet, and the former has a lower energy. In addition, compared with Cap-(9, 0) CNTs, the C adatoms on C30 causes spin polarization phenomenon and Cap- (9, 0)-Def [6, 6] has more spin electrons than Cap-(9, 0)-Def [5, 6] structure. Moreover, different adsorb defects reveal different electron accumulation. This finding shows that spin polarization of the asymmetric structure can be adjusted by introducing adatom defects.

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STABLE STRUCTURES, ELECTRIC AND MAGNETIC PROPERTIES OF NANOPARTICLES COn(n = 1-6) CLUSTERS: FIRST-PRINCIPLES CALCULATIONS

International Journal of Modern Physics B ◽

10.1142/s0217979213620075 ◽

2013 ◽

Vol 27 (15) ◽

pp. 1362007

Author(s):

JUN LIU ◽

SHENG-BIAO TAN ◽

HUI-NING DONG

Keyword(s):

Magnetic Properties ◽

Ground State ◽

First Principles ◽

Lower Energy ◽

Magnetic Moments ◽

Molecular Orbitals ◽

First Principles Calculations ◽

Half Metallicity ◽

Ground State Structures ◽

Stable Structures

The ground state geometric structures of the nanoparticles or clusters CO n(n = 1-6) were given based on the first-principles calculations. Then the magnetic properties of the clusters CO n(n = 1-6) and ( CO n)-2(n = 1-6) were calculated in system. Results show that their ground state structures are closely related to the numbers of O-ions. These clusters have no magnetic moments and half-metallicity if they are electroneutral. However, they have magnetic moments if they have positive or negative charges. The total magnetic moments of the clusters ( CO n)-2(n = 1-6, but n≠3) are all 2.0000 μB, and all their ions have contributions to the total magnetic moments. The main reason is that the molecular orbitals with lower energy filled with paired electrons and the molecular orbitals with higher energy are occupied by two electrons in parallel.

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Orbitally dominated Rashba-Edelstein effect in noncentrosymmetric antiferromagnets

Nature Communications ◽

10.1038/s41467-019-13367-z ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 9

Author(s):

Leandro Salemi ◽

Marco Berritta ◽

Ashis K. Nandy ◽

Peter M. Oppeneer

Keyword(s):

Spin Polarization ◽

First Principles ◽

Magnetic Order ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

First Principles Calculations ◽

Local Magnetization ◽

Spintronic Devices ◽

Current Pulses ◽

Electric Current Pulses

AbstractEfficient manipulation of magnetic order with electric current pulses is desirable for achieving fast spintronic devices. The Rashba-Edelstein effect, wherein spin polarization is electrically induced in noncentrosymmetric systems, provides a mean to achieve staggered spin-orbit torques. Initially predicted for spin, its orbital counterpart has been disregarded up to now. Here we report a generalized Rashba-Edelstein effect, which generates not only spin polarization but also orbital polarization, which we find to be far from being negligible. We show that the orbital Rashba-Edelstein effect does not require spin-orbit coupling to exist. We present first-principles calculations of the frequency-dependent spin and orbital Rashba-Edelstein tensors for the noncentrosymmetric antiferromagnets CuMnAs and Mn$${}_{2}$$2Au. We show that the electrically induced local magnetization can exhibit Rashba-like or Dresselhaus-like symmetries, depending on the magnetic configuration. We compute sizable induced magnetizations at optical frequencies, which suggest that electric-field driven switching could be achieved at much higher frequencies.

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First Principles Investigation of Divacancy in SiC Polytypes for Solid State Qubit Application

Materials Science Forum ◽

10.4028/www.scientific.net/msf.778-780.499 ◽

2014 ◽

Vol 778-780 ◽

pp. 499-502 ◽

Cited By ~ 3

Author(s):

Krisztián Szász ◽

Viktor Ivády ◽

Erik Janzén ◽

Ádám Gali

Keyword(s):

Density Functional Theory ◽

Excited States ◽

Ground State ◽

First Principles ◽

Density Functional ◽

Zero Field ◽

Polarization Phenomenon ◽

Zero Field Splitting ◽

Nuclear Spin Polarization ◽

Functional Theory

We calculated the hyperfine structure and the zero-field splitting parameters of divacancies in 3C, 4Hand 6HSiC in the ground state and in the excited state for 4HSiC within the framework of density functional theory. Besides that our calculations provide identification of the defect in different polytypes, we can find some carbon atoms next to the divacancy that of the spin polarizations are similar in the ground and excited states. This coherent nuclear spin polarization phenomenon can be the base to utilize13C spins as quantum memory.

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First principles calculations of the structural, electronic, magnetic, and thermodynamic properties of the Nd2MgGe2 and Gd2MgGe2 intermetallic compounds

Scientific Reports ◽

10.1038/s41598-021-89042-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

S. Menouer ◽

O. Miloud Abid ◽

A. Benzair ◽

A. Yakoubi ◽

H. Khachai ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermodynamic Properties ◽

Ground State ◽

First Principles ◽

Essential Role ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Rare Earth Compounds ◽

First Principles Calculations ◽

Antiferromagnetic Ground State

AbstractIn recent years the intermetallic ternary RE2MgGe2 (RE = rare earth) compounds attract interest in a variety of technological areas. We therefore investigate in the present work the structural, electronic, magnetic, and thermodynamic properties of Nd2MgGe2 and Gd2MgGe2. Spin–orbit coupling is found to play an essential role in realizing the antiferromagnetic ground state observed in experiments. Both materials show metallicity and application of a Debye-Slater model demonstrates low thermal conductivity and little effects of the RE atom on the thermodynamic behavior.

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Ferromagnetic Dirac Half-Metallicity in Transition Metal Embedded Honeycomb Borophene

Physical Chemistry Chemical Physics ◽

10.1039/d1cp01708j ◽

2021 ◽

Author(s):

Yanxia Wang ◽

Xue Jiang ◽

Yi Wang ◽

Jijun Zhao

Keyword(s):

Transition Metal ◽

First Principles ◽

Valence Electron ◽

Two Dimensional ◽

First Principles Calculations ◽

Next Generation ◽

Half Metallicity ◽

Counting Rule ◽

Spintronic Devices ◽

Electron Counting

Exploring two-dimensional (2D) ferromagnetic materials with intrinsic Dirac half-metallicity is crucial for the development of next-generation spintronic devices. Based on first-principles calculations, here we propose a simple valence electron-counting rule...

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Electronic, structural and ground state properties of 3d transition metal mononitrides: A first principles study

10.1063/1.4810269 ◽

2013 ◽

Author(s):

R. Rajeswarapalanichamy ◽

M. Santhosh ◽

G. Sudha Priyanga ◽

A. T. Asvini Meenaatci ◽

S. Kanagaprabha

Keyword(s):

Transition Metal ◽

Ground State ◽

First Principles ◽

First Principles Study ◽

Ground State Properties

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VUV FRAGMENTATION OF SOME HYDROFLUOROCARBON CATIONS STUDIED USING COINCIDENCE TECHNIQUES

Surface Review and Letters ◽

10.1142/s0218625x0200204x ◽

2002 ◽

Vol 09 (01) ◽

pp. 153-158 ◽

Cited By ~ 5

Author(s):

WEIDONG ZHOU ◽

D. P. SECCOMBE ◽

R. Y. L. CHIM ◽

R. P. TUCKETT

Keyword(s):

Kinetic Energy ◽

Ab Initio ◽

Ground State ◽

Lower Energy ◽

Lone Pair ◽

Electronic States ◽

Photoelectron Spectra ◽

Highest Occupied Molecular Orbital ◽

Impulsive Model ◽

Lone Pair Electrons

Threshold photoelectron–photoion coincidence (TPEPICO) spectroscopy has been used to investigate the decay dynamics of the valence electronic states of the parent cation of several hydrofluorocarbons (HFC), based on fluorine-substituted ethane, in the energy range 11–25 eV. We present data for CF 3– CHF 2, CF 3– CH 2 F , CF 3– CH 3 and CHF 2– CH 3. The threshold photoelectron spectra (TPES) of these molecules show a common feature of a broad, relatively weak ground state, associated with electron removal from the highest-occupied molecular orbital (HOMO) having mainly C–C σ-bonding character. Adiabatic and vertical ionisation energies for the HOMO of the four HFCs are presented, together with corresponding values from ab initio calculations. For those lower-energy molecular orbitals associated with non-bonding fluorine 2pπ lone pair electrons, these electronic states of the HFC cation decay impulsively by C–F bond fission with considerable release of translational kinetic energy. Appearance energies are presented for formation of the daughter cation formed by such a process (e.g. CF 3– CHF +), together with ab initio energies of the corresponding dissociation channel (e.g. CF 3– CHF + + F ). Values for the translational kinetic energy released are compared with the predictions of a pure-impulsive model.

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First-principles study of electronic structure and ground-state properties of alkali-metal sulfides – Li2S, Na2S, K2S and Rb2S

physica status solidi (b) ◽

10.1002/pssb.200642506 ◽

2007 ◽

Vol 244 (4) ◽

pp. 1337-1346 ◽

Cited By ~ 44

Author(s):

R. D. Eithiraj ◽

G. Jaiganesh ◽

G. Kalpana ◽

M. Rajagopalan

Keyword(s):

Electronic Structure ◽

Alkali Metal ◽

Ground State ◽

First Principles ◽

Metal Sulfides ◽

First Principles Study ◽

Ground State Properties

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Investigation of spin polarization in Gd-doped ZnO films for high-performance organic spintronic devices

Materials Science and Engineering B ◽

10.1016/j.mseb.2021.115536 ◽

2022 ◽

Vol 276 ◽

pp. 115536

Author(s):

Norhidayah Che Ani ◽

Mohd Zainizan Sahdan ◽

Nafarizal Nayan ◽

Feri Adriyanto ◽

Kusnanto Mukti Wibowo

Keyword(s):

Spin Polarization ◽

High Performance ◽

Zno Films ◽

Spintronic Devices ◽

Doped Zno

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Spin Polarization Properties of Pentagonal PdSe2 Induced by 3D Transition-Metal Doping: First-Principles Calculations

Materials ◽

10.3390/ma11112339 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2339 ◽

Cited By ~ 7

Author(s):

Xiuwen Zhao ◽

Bin Qiu ◽

Guichao Hu ◽

Weiwei Yue ◽

Junfeng Ren ◽

...

Keyword(s):

Transition Metal ◽

Spin Polarization ◽

First Principles ◽

Magnetic Moments ◽

First Principles Calculations ◽

Density Distributions ◽

Metal Atoms ◽

Transition Metal Atoms ◽

Theoretical Investigations ◽

Densities Of States

The electronic structure and spin polarization properties of pentagonal structure PdSe2 doped with transition metal atoms are studied through first- principles calculations. The theoretical investigations show that the band gap of the PdSe2 monolayer decreases after introducing Cr, Mn, Fe and Co dopants. The projected densities of states show that p-d orbital couplings between the transition metal atoms and PdSe2 generate new spin nondegenerate states near the Fermi level which make the system spin polarized. The calculated magnetic moments, spin density distributions and charge transfer of the systems suggest that the spin polarization in Cr-doped PdSe2 will be the biggest. Our work shows that the properties of PdSe2 can be modified by doping transition metal atoms, which provides opportunity for the applications of PdSe2 in electronics and spintronics.

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