scholarly journals Spin-Polarized Electron Transmission in DNA-Like Systems

Biomolecules ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 49 ◽  
Author(s):  
Miguel A. Sierra ◽  
David Sánchez ◽  
Rafael Gutierrez ◽  
Gianaurelio Cuniberti ◽  
Francisco Domínguez-Adame ◽  
...  
Keyword(s):  
Orbit Coupling ◽  
Theoretical Modelling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Chiral Molecules ◽  
Electronic Density ◽  
Coupling Interaction ◽  
Molecular Systems ◽  
Electron Transmission ◽  
Spin Polarized

The helical distribution of the electronic density in chiral molecules, such as DNA and bacteriorhodopsin, has been suggested to induce a spin–orbit coupling interaction that may lead to the so-called chirality-induced spin selectivity (CISS) effect. Key ingredients for the theoretical modelling are, in this context, the helically shaped potential of the molecule and, concomitantly, a Rashba-like spin–orbit coupling due to the appearance of a magnetic field in the electron reference frame. Symmetries of these models clearly play a crucial role in explaining the observed effect, but a thorough analysis has been largely ignored in the literature. In this work, we present a study of these symmetries and how they can be exploited to enhance chiral-induced spin selectivity in helical molecular systems.

Ab initio spin–orbit coupling SCF calculation of parity-violating energy of chiral molecules

2002 ◽  
Vol 589-590 ◽  
pp. 183-193 ◽  
Author(s):  
Takeshi Kitayama ◽  
Hiroshi Kiyonaga ◽  
Kenji Morihashi ◽  
Ohgi Takahashi ◽  
Osamu Kikuchi
Keyword(s):  
Ab Initio ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Chiral Molecules

SPONTANEOUS SPIN POLARIZATION OF ELECTRONS IN SiGe/Si HETEROSTRUCTURES

2010 ◽  
Vol 09 (05) ◽  
pp. 503-509
Author(s):  
A. JOHN PETER
Keyword(s):  
Zero Magnetic Field ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Resonant Level ◽  
Electron Transmission ◽  
Rashba Spin ◽  
Spin Polarized ◽  
Spin Filters ◽  
Spin Injectors ◽  
The One

The spin-dependent electron transmission phenomenon in an SiGe/Si/SiGe resonant semiconductor heterostructure is employed theoretically to investigate the output transmission current polarization at zero magnetic field. Transparency of electron transmission is calculated as a function of electron energy as well as the well width, within the one electron band approximation along with the spin-orbit interaction. Enhanced spin-polarized resonant tunneling in the heterostructure due to Dresselhaus and Rashba spin-orbit coupling induced splitting of the resonant level is observed. We predict that a spin-polarized current spontaneously emerges in this heterostructure and we estimate theoretically that the polarization can reach 100%. This effect could be employed in the fabrication of spin filters, spin injectors, and detectors based on nonmagnetic semiconductors.

scholarly journals The Importance of Spin State in Chiral Supramolecular Electronics

2021 ◽  
Vol 9 ◽  
Author(s):  
Ana M. Garcia ◽  
Gabriel Martínez ◽  
Amparo Ruiz-Carretero
Keyword(s):  
Organic Electronics ◽  
Spin State ◽  
Organic Materials ◽  
Spin Injection ◽  
Inorganic Materials ◽  
Orbit Coupling ◽  
Light Illumination ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Chiral Molecules

The field of spintronics explores how magnetic fields can influence the properties of organic and inorganic materials by controlling their electron’s spins. In this sense, organic materials are very attractive since they have small spin-orbit coupling, allowing long-range spin-coherence over times and distances longer than in conventional metals or semiconductors. Usually, the small spin-orbit coupling means that organic materials cannot be used for spin injection, requiring ferromagnetic electrodes. However, chiral molecules have been demonstrated to behave as spin filters upon light illumination in the phenomenon described as chirality-induced spin selectivity (CISS) effect. This means that electrons of certain spin can go through chiral assemblies of molecules preferentially in one direction depending on their handedness. This is possible because the lack of inversion symmetry in chiral molecules couples with the electron’s spin and its linear momentum so the molecules transmit the one preferred spin. In this respect, chiral semiconductors have great potential in the field of organic electronics since when charge carriers are created, a preferred spin could be transmitted through a determined handedness structure. The exploration of the CISS effect in chiral supramolecular semiconductors could add greatly to the efforts made by the organic electronics community since charge recombination could be diminished and charge transport improved when the spins are preferentially guided in one specific direction. This review outlines the advances in supramolecular chiral semiconductors regarding their spin state and its influence on the final electronic properties.

Electron correlation and spin-orbit coupling effects in scandium intermetallic compounds ScTM (TM = Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag and Au)

2017 ◽  
Vol 31 (32) ◽  
pp. 1750263 ◽  
Author(s):  
Rashid Iqbal ◽  
Zahid Ali ◽  
S. Jalali-Asadabadi ◽  
Iftikhar Ahmad
Keyword(s):  
Intermetallic Compounds ◽  
Density Functional ◽  
Structural Parameters ◽  
Orbit Coupling ◽  
Ferromagnetic Phase ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Exchange Correlation ◽  
Spin Polarized ◽  
Highly Correlated

Spin-polarized density functional calculations are performed to study the correlation and spin-orbit coupling (SOC) effects in scandium intermetallic compounds viz. ScTM (TM[Formula: see text]=[Formula: see text]Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag and Au) using FP-LAPW[Formula: see text]+[Formula: see text]lo method. The LDA, LDA[Formula: see text]+[Formula: see text]U and LDA[Formula: see text]+[Formula: see text]U[Formula: see text]+[Formula: see text]SOC exchange-correlation functionals are used to calculate the structural parameters and we found that the LDA[Formula: see text]+[Formula: see text]U results are consistent with the experiments. The electronic properties reveal that these compounds are metallic in nature. Correlations effects are determined using the U/W ratio and we found that ScCo, ScIr, ScPd, ScPt, ScCu and ScAg are highly correlated compounds, whereas ScRh, ScNi and ScAu are intermediately correlated compounds. Furthermore, stable magnetic phase for each compound is optimized, which reveals that ScCo, ScRh, ScPd, ScPt and ScCu are stable in ferromagnetic phase, ScIr, ScNi and ScAu are anti-ferromagnetic, whereas ScAg is a nonmagnetic material.

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