Ferromagnetism and spin-polarized charge carriers inIn2O3thin films

The quantum Hall effect, observed in a two-dimensional (2D) electron gas subjected to a perpendicular magnetic field, imposes a 1D-like chiral, downstream, transport of charge carriers along the sample edges. Although this picture remains valid for electrons and Laughlin’s fractional quasiparticles, it no longer holds for quasiparticles in the so-called hole-conjugate states. These states are expected, when disorder and interactions are weak, to harbor upstream charge modes. However, so far, charge currents were observed to flow exclusively downstream in the quantum Hall regime. Studying the canonical spin-polarized and spin-unpolarized v = 2/3 hole-like states in GaAs-AlGaAs heterostructures, we observed a significant upstream charge current at short propagation distances in the spin unpolarized state.

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Tunneling of spin-polarized charge carriers in La0.8Ag0.1MnO3+δ film with variant structure: Magnetotransport and magnetooptical data

Technical Physics Letters ◽

10.1134/1.1969772 ◽

2005 ◽

Vol 31 (6) ◽

pp. 484-487 ◽

Cited By ~ 8

Author(s):

Yu. P. Sukhorukov ◽

A. V. Telegin ◽

E. A. Gan’shina ◽

N. N. Loshkareva ◽

A. R. Kaul’ ◽

...

Keyword(s):

Charge Carriers ◽

Spin Polarized ◽

Variant Structure

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TRANSITION OF BIPOLARON TO POLARONS INDUCED BY MAGNETIC IMPURITIES IN CONJUGATED POLYMERS

International Journal of Modern Physics B ◽

10.1142/s0217979211100400 ◽

2011 ◽

Vol 25 (12) ◽

pp. 1601-1610

Author(s):

X. J. LIU ◽

Z. AN ◽

S. J. XIE

Keyword(s):

Conjugated Polymers ◽

Conjugated Polymer ◽

Dynamic Method ◽

Optoelectronic Devices ◽

Charge Carriers ◽

Composite Particles ◽

Magnetic Impurities ◽

Internal Structures ◽

Spin Polarized ◽

Pass Through

Both polarons and bipolarons are composite particles with internal structures in nondegenerate conjugated polymers. A bipolaron is a spinless species with charge ±2|e|, while a polaron is a spin-bearing one (spin 1/2, charge ±|e|). Serving as charge carriers, they play an important role in the transport properties of polymer-based optoelectronic devices. By using a nonadiabatic dynamic method, the motion of a bipolaron under an external electric field is theoretically investigated in a conjugated polymer with magnetic impurities. Our results show that a bipolaron can pass through the magnetic impurities, or break down into two polarons with different spins, or be trapped by the magnetic impurities, depending on the width of the impurity region. When the width of the impurity region is comparable to the polaron width, the bipolaron is transformed into two polarons easily. As a polaron and a bipolaron possess different spin characteristics, the decomposition of bipolarons induced by the magnetic impurities may have important effect on the spin polarized transportation.

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Shift of the collective mode of polarized graphene on a substrate using spin-sensitive response theory

Lithuanian Journal of Physics ◽

10.3952/physics.v59i1.3939 ◽

2019 ◽

Vol 59 (1) ◽

Cited By ~ 1

Author(s):

Dominik Kreil ◽

Michaela Haslhofer ◽

Helga M. Böhm

Keyword(s):

Collective Mode ◽

Near Field ◽

Plasmon Mode ◽

Charge Carriers ◽

Semiconductor Heterostructures ◽

Response Functions ◽

Interband Transitions ◽

S Wave ◽

Minority Spin ◽

Spin Polarized

The growing precision of optical and scattering experiments necessitates a better understanding of the influence of damping onto the collective mode of sheet electrons. As spin-polarized systems are of particular interest for spintronic applications, we here report spin-sensitive linear response functions of graphene, which give access to chargeand spin-density related excitations. We further calculate the reflectivity of graphene on an SiO2 surface, a setup used in s-wave scanning near-field microscopy. Increasing the partial spin-polarization of the graphene charge carriers leads to a significant broadening and shift of the plasmon mode, due to single-particle interband transitions of the minority spin carriers. We also predict an antiresonance in the longitudinal magnetic response function, similar to that of semiconductor heterostructures.

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LOW-DIMENSIONAL SOURCES OF SPIN-POLARIZED CHARGE CARRIERS

Physics, Chemistry and Application of Nanostructures ◽

10.1142/9789812701947_0061 ◽

2005 ◽

Author(s):

S. A. IGNATENKO ◽

V. E. BORISENKO

Keyword(s):

Charge Carriers ◽

Spin Polarized ◽

Low Dimensional

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Accumulation of spin-polarized states of charge carriers and a spintronic battery

Low Temperature Physics ◽

10.1063/10.0001370 ◽

2020 ◽

Vol 46 (7) ◽

pp. 724-733

Author(s):

L. А. Pastur ◽

V. V. Slavin ◽

A. V. Yanovsky

Keyword(s):

Charge Carriers ◽

Spin Polarized

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New mechanism and exact theory of superconductivity from strong repulsive interaction

Science Advances ◽

10.1126/sciadv.abh2233 ◽

2021 ◽

Vol 7 (30) ◽

pp. eabh2233

Author(s):

Valentin Crépel ◽

Liang Fu

Keyword(s):

Pairing Symmetry ◽

Charge Carriers ◽

General Mechanism ◽

Repulsive Interaction ◽

Fermi Systems ◽

Fermi Temperature ◽

Spin Polarized ◽

Atomic Limit ◽

Theory Of Superconductivity ◽

Quantitative Formula

We introduce a general mechanism for superconductivity in Fermi systems with strong repulsive interaction. Because kinetic terms are small compared to the bare repulsion, the dynamics of charge carriers is constrained by the presence of other nearby carriers. By treating kinetic terms as a perturbation around the atomic limit, we show that pairing can be induced by correlated multiparticle tunneling processes that favor two itinerant carriers to be close together. Our analytically controlled theory provides a quantitative formula relating Tc to microscopic parameters, with maximum Tc reaching about 10% of the Fermi temperature. Our work demonstrates a powerful method for studying strong coupling superconductivity with unconventional pairing symmetry. It also offers a realistic new route to realizing finite angular momentum superfluidity of spin-polarized fermions in optical lattice.

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Structural, microstructural, transport, and magnetotransport properties of nanostructured La0.7Sr0.3MnO3 manganites synthesized by coprecipitation

Journal of Materials Research ◽

10.1557/jmr.2010.0229 ◽

2010 ◽

Vol 25 (9) ◽

pp. 1799-1802 ◽

Cited By ~ 22

Author(s):

P.S. Solanki ◽

R.R. Doshi ◽

U.D. Khachar ◽

M.V. Vagadia ◽

A.B. Ravalia ◽

...

Keyword(s):

Low Temperature ◽

High Field ◽

Room Temperature ◽

Single Phase ◽

Sintering Temperature ◽

Strong Dependence ◽

Charge Carriers ◽

Spin Polarized ◽

Spin Dependent Scattering ◽

Coprecipitation Route

The structural, transport, and magnetotransport properties of single-phase, homogeneous nanostructured La0.7Sr0.3MnO3 (LSMO) manganites synthesized by the coprecipitation route were investigated and the effect of sintering temperature on the microstructure of LSMO compounds was studied. A strong dependence of transport and magnetotransport behavior on the microstructure and nature of grain boundaries has been observed in the single-phase LSMO sintered at various temperatures. High-field magnetoresistance (HFMR) at room temperature is found to increase [13% (LS6) to 25% (LS9)] while low temperature (5 K) magnetoresistance decreases [75% (LS6) to 46% (LS9)] under 9 T field with increase in sintering temperature, which has been attributed to the spin-polarized tunneling and spin-dependent scattering of charge carriers.

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Detector strategies for environmental scanning electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131115 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1296-1297

Author(s):

Klaus-Ruediger Peters

Keyword(s):

High Vacuum ◽

Environmental Scanning Electron Microscopy ◽

Charge Carriers ◽

Environmental Scanning ◽

Surface Information ◽

X Ray ◽

Detector Electrode ◽

Electrons And Ions ◽

Low Energy Electrons ◽

Environmental Sem

Environmental SEM operate at specimen chamber pressures of ∼20 torr (2.7 kPa) allowing stabilization of liquid water at room temperature, working on rugged insulators, and generation of an environmental secondary electron (ESE) signal. All signals available in conventional high vacuum instruments are also utilized in the environmental SEM, including BSE, SE, absorbed current, CL, and X-ray. In addition, the ESEM allows utilization of the flux of charge carriers as information, providing exciting new signal modes not available to BSE imaging or to conventional high vacuum SEM.In the ESEM, at low vacuum, SE electrons are collected with a “gaseous detector”. This detector collects low energy electrons (and ions) with biased wires or plates similar to those used in early high vacuum SEM for SE detection. The detector electrode can be integrated into the first PLA or positioned at any other place resulting in a versatile system that provides a variety of surface information.

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