Spin Polarization of Composite Fermions: Measurements of the Fermi Energy

1999 ◽  
Vol 82 (18) ◽  
pp. 3665-3668 ◽  
Author(s):  
I. V. Kukushkin ◽  
K. v. Klitzing ◽  
K. Eberl
Keyword(s):  
Spin Polarization ◽  
Fermi Energy ◽  
Composite Fermions

Spin Polarized Transport through Structures Consist of the Ferromagnetic Semiconductor in Presence of a Inhomogeneous Magnetic Field

2011 ◽  
Vol 194-196 ◽  
pp. 679-682
Author(s):  
Zahra Bamshad
Keyword(s):  
Magnetic Field ◽  
Spin Polarization ◽  
Fermi Energy ◽  
Magnetic Tunnel Junction ◽  
Inhomogeneous Magnetic Field ◽  
Spin Polarized ◽  
Polarized Transport ◽  
Dimensional Electron Gas ◽  
Spin Electronic ◽  
Spin Polarized Transport

The spin-polarized transport is investigated in a magnetic tunnel junction which consists of two ferromagnetic electrodes separated by a magnetic barrier and a nonmagnetic metallic spacer placed in distance above the two dimensional electron gas (2DEG) in presence of an inhomogeneous external modulated magnetic field and a perpendicular wave vector dependent effective potential. Based on the transfer matrix method and the nearly-free-electron approximation the dependence of the conductance and spin polarization on the Fermi energy of the electrons are studied theoretically the. strong oscillations with large amplitude investigated in spin polarization in terms of the Fermi energy due to the inhomogeneous magnetic field. The conductance in terms of the Fermi energy shows no oscillation in low energy but has a strong pick in middle region. this results may be useful for the development of spin electronic devices based on coherent transport, or may be used as a tunable spin-filter.

scholarly journals Design Considerations for Oligo(p-Phenyleneethynylene) Organic Radicals in Molecular Junctions

2020 ◽  
Author(s):  
Martin Sebastian Zöllner ◽  
Rukan Nasri ◽  
Haitao Zhang ◽  
Carmen Herrmann
Keyword(s):  
Spin Polarization ◽  
Single Molecule ◽  
Fermi Energy ◽  
Organic Radicals ◽  
Stable Radical ◽  
Design Consideration ◽  
Dispersion Interactions ◽  
Electron Transmission ◽  
Design Considerations ◽  
Spin Delocalization

Spin polarization in the electron transmission of radicals is important for understanding single-molecule conductance experiments focusing on shot noise, Kondo properties or magnetoresistance. We study how stable radical substituents can affect such spin polarization when attached to oligo(p- phenyleneethynylene) (OPE) backbones. We find that it is not straightforward to translate the spin density on a stable radical substituent into spin-dependent transmission for the para-connected wires under study here, owing to increased steric interactions compared with meta-connected wires, and a resulting twisting of the radical substituent and OPE π systems. The most promising example is a t-butyl nitroxide substituent, which, despite little pronounced spin delocalization onto the backbone, yields a spin-dependent transmission feature which one might be able to shift towards the Fermi energy by additional substituents. We also find that for bulkier substituents, dispersion interactions with the substituent can lead to twisting of one of the outer OPE rings, reducing the overall conductance. As a further potential design consideration, attaching radicals via linkers might increase the possibilities for spin-dependent intermolecular and molecule-electrode interactions.

scholarly journals Room-temperature observation of high-spin polarization of epitaxial CrO2(100) island films at the Fermi energy

2002 ◽  
Vol 80 (22) ◽  
pp. 4181-4183 ◽  
Author(s):  
Yu. S. Dedkov ◽  
M. Fonine ◽  
C. König ◽  
U. Rüdiger ◽  
G. Güntherodt ◽  
...  
Keyword(s):  
Spin Polarization ◽  
High Spin ◽  
Fermi Energy ◽  
Room Temperature ◽  
Temperature Observation ◽  
High Spin Polarization ◽  
Island Films

scholarly journals Design Considerations for Oligo(p-Phenyleneethynylene) Organic Radicals in Molecular Junctions

2020 ◽  
Author(s):  
Martin Sebastian Zöllner ◽  
Rukan Nasri ◽  
Haitao Zhang ◽  
Carmen Herrmann
Keyword(s):  
Spin Polarization ◽  
Single Molecule ◽  
Fermi Energy ◽  
Organic Radicals ◽  
Stable Radical ◽  
Design Consideration ◽  
Dispersion Interactions ◽  
Electron Transmission ◽  
Design Considerations ◽  
Spin Delocalization

Spin polarization in the electron transmission of radicals is important for understanding single-molecule conductance experiments focusing on shot noise, Kondo properties or magnetoresistance. We study how stable radical substituents can affect such spin polarization when attached to oligo(p- phenyleneethynylene) (OPE) backbones. We find that it is not straightforward to translate the spin density on a stable radical substituent into spin-dependent transmission for the para-connected wires under study here, owing to increased steric interactions compared with meta-connected wires, and a resulting twisting of the radical substituent and OPE π systems. The most promising example is a t-butyl nitroxide substituent, which, despite little pronounced spin delocalization onto the backbone, yields a spin-dependent transmission feature which one might be able to shift towards the Fermi energy by additional substituents. We also find that for bulkier substituents, dispersion interactions with the substituent can lead to twisting of one of the outer OPE rings, reducing the overall conductance. As a further potential design consideration, attaching radicals via linkers might increase the possibilities for spin-dependent intermolecular and molecule-electrode interactions.

scholarly journals Design Considerations for Oligo(p-Phenyleneethynylene) Organic Radicals in Molecular Junctions

2020 ◽  
Author(s):  
Martin Sebastian Zöllner ◽  
Rukan Nasri ◽  
Haitao Zhang ◽  
Carmen Herrmann
Keyword(s):  
Spin Polarization ◽  
Single Molecule ◽  
Fermi Energy ◽  
Organic Radicals ◽  
Stable Radical ◽  
Design Consideration ◽  
Dispersion Interactions ◽  
Electron Transmission ◽  
Design Considerations ◽  
Spin Delocalization

Spin polarization in the electron transmission of radicals is important for understanding single-molecule conductance experiments focusing on shot noise, Kondo properties or magnetoresistance. We study how stable radical substituents can affect such spin polarization when attached to oligo(p- phenyleneethynylene) (OPE) backbones. We find that it is not straightforward to translate the spin density on a stable radical substituent into spin-dependent transmission for the para-connected wires under study here, owing to increased steric interactions compared with meta-connected wires, and a resulting twisting of the radical substituent and OPE π systems. The most promising example is a t-butyl nitroxide substituent, which, despite little pronounced spin delocalization onto the backbone, yields a spin-dependent transmission feature which one might be able to shift towards the Fermi energy by additional substituents. We also find that for bulkier substituents, dispersion interactions with the substituent can lead to twisting of one of the outer OPE rings, reducing the overall conductance. As a further potential design consideration, attaching radicals via linkers might increase the possibilities for spin-dependent intermolecular and molecule-electrode interactions.

Temperature dependence of the spin polarization of composite fermions

JETP Letters ◽  
1999 ◽  
Vol 70 (11) ◽  
pp. 730-735 ◽  
Author(s):  
I. V. Kukushkin ◽  
K. von Klitzing ◽  
K. G. Levchenko ◽  
Yu. E. Lozovik
Keyword(s):  
Temperature Dependence ◽  
Spin Polarization ◽  
Composite Fermions

scholarly journals Full Valley and Spin Polarizations in Strained Graphene with Rashba Spin Orbit Coupling and Magnetic Barrier

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Qing-Ping Wu ◽  
Zheng-Fang Liu ◽  
Ai-Xi Chen ◽  
Xian-Bo Xiao ◽  
Zhi-Min Liu
Keyword(s):  
Spin Polarization ◽  
Fermi Energy ◽  
Band Gaps ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Magnetic Barrier ◽  
Single Spin ◽  
Rashba Spin ◽  
Strained Graphene

Abstract We propose a graphene-based full valley- and spin-polarization device based on strained graphene with Rashba spin orbit coupling and magnetic barrier. The underlying mechanism is the coexistence of the valley and single spin band gaps in a certain Fermi energy. By aligning the Fermi energy in the valley and single spin band gaps, remarkable valley- and spin-polarization currents can be accessed.

scholarly journals Spin polarization of composite fermions and particle-hole symmetry breaking

2014 ◽  
Vol 90 (8) ◽  
Author(s):  
Yang Liu ◽  
S. Hasdemir ◽  
A. Wójs ◽  
J. K. Jain ◽  
L. N. Pfeiffer ◽  
...  
Keyword(s):  
Symmetry Breaking ◽  
Spin Polarization ◽  
Composite Fermions

NEGATIVE MAGNETORESISTANCE OF A SILICON 2DEG UNDER IN-PLANE MAGNETIC FIELD DUE TO SPIN-SPLITTING OF UPPER SUBBANDS

2009 ◽  
Vol 23 (12n13) ◽  
pp. 2938-2942
Author(s):  
K. TAKASHINA ◽  
Y. NIIDA ◽  
V. T. RENARD ◽  
A. FUJIWARA ◽  
T. FUJISAWA ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Quantum Well ◽  
Spin Polarization ◽  
Fermi Energy ◽  
Electron System ◽  
Negative Magnetoresistance ◽  
Spin Splitting ◽  
Dimensional Electron ◽  
Negative Contribution ◽  
Dimensional Electron System

We examine the effect of an in-plane magnetic field on the resistance of a 2-dimensional electron system confined in a silicon quantum well when the Fermi energy is tuned through the upper valley-subband edge while the electrons are otherwise valley-polarized. In contrast to previous experiments on valley-degenerate systems which only showed positive magnetoresistance, when the Fermi energy is at or near the upper valley-subband edge, the magnetoresistance is found to show a distinct negative contribution which is interpreted as being due to spin polarization of the upper valley-subband.

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