Nuclear spin polarization by out-of-plane spin injection from ferromagnet into an InAs heterostructure

AbstractWe have investigated an InAs channel Hall-bar structure with ferromagnetic spin injector in one of the current terminals. After magnetizing the Fe electrode, spin polarized electrons are injected through the edge of the isolation mesa structure and the anomalous Hall voltage is observed, when electrons are injected from the ferromagnetic terminal. However, when electrons are injected from the non-magnetic metal (Ti/Au) of opposite terminal, the Hall voltage disappeared to the variation error level due to the fabrication imperfections. This result suggests the possibility that out-of-plane spin injection from the channel edge lead to perpendicular nuclear magnetic field. It is presumably caused by nuclear spin polarization in InAs channel near the spin source edge through Overhauser effect. The estimated internal magnetic field was 2000 Gauss.

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Magnetic field dependence of fluorine-19 nuclear spin polarization. The system tetrafluorobenzoquinone-tetrafluorohydroquinone

Journal of the American Chemical Society ◽

10.1021/ja00386a005 ◽

1982 ◽

Vol 104 (22) ◽

pp. 5878-5883 ◽

Cited By ~ 1

Author(s):

Richard S. Hutton ◽

Heinz D. Roth ◽

Marcia L. Manion Schilling ◽

Anthony M. Trozzolo ◽

Thomas M. Leslie

Keyword(s):

Magnetic Field ◽

Spin Polarization ◽

Field Dependence ◽

Nuclear Spin ◽

Magnetic Field Dependence ◽

Nuclear Spin Polarization

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Nuclear spin-polarization in single InGaAs quantum dots through electrical and optical spin-injection in spin-LEDs

physica status solidi (c) ◽

10.1002/pssc.201000822 ◽

2011 ◽

Vol 8 (4) ◽

pp. 1157-1160 ◽

Cited By ~ 1

Author(s):

M. Hetterich ◽

P. Asshoff ◽

G. Wüst ◽

A. Merz ◽

H. Kalt

Keyword(s):

Quantum Dots ◽

Spin Polarization ◽

Nuclear Spin ◽

Spin Injection ◽

Nuclear Spin Polarization

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p-shell carrier assisted dynamic nuclear spin polarization in single quantum dots at zero external magnetic field

Physical Review B ◽

10.1103/physrevb.93.125306 ◽

2016 ◽

Vol 93 (12) ◽

Cited By ~ 2

Author(s):

C. F. Fong ◽

Y. Ota ◽

E. Harbord ◽

S. Iwamoto ◽

Y. Arakawa

Keyword(s):

Magnetic Field ◽

Quantum Dots ◽

External Magnetic Field ◽

Spin Polarization ◽

Nuclear Spin ◽

Single Quantum ◽

Nuclear Spin Polarization ◽

Single Quantum Dots

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Optical Pumping and Optical Detection of Spin-Polarized Electrons in a Conduction Band

Canadian Journal of Physics ◽

10.1139/p71-222 ◽

1971 ◽

Vol 49 (14) ◽

pp. 1850-1860 ◽

Cited By ~ 33

Author(s):

R. R. Parsons

Keyword(s):

Magnetic Field ◽

Conduction Band ◽

Spin Polarization ◽

Optical Pumping ◽

Polarized Light ◽

Degree Of Polarization ◽

Polarized Electrons ◽

Excitation Light ◽

Circularly Polarized Light ◽

Spin Polarized

Spin-polarized electrons are created in the conduction band of p-type GaSb by excitation with σ+ or σ− circularly polarized light. The degree of polarization of the photoluminescence is used to measure the optically pumped spin polarization. The measurements as a function of transverse magnetic field yield the spin-relaxation time and the lifetime of the photocreated electrons. The degree of polarization oscillates as a function of the photon energy of the excitation light. This effect is associated with mechanisms of rapid energy loss involving optical and acoustical phonons. The optical pumping is studied as a function of temperature in the range 3.5 °K ≤ T ≤ 11 °K. A maximum spin polarization [Formula: see text] is obtained at [Formula: see text]. The efficiency of the optical pumping is significantly increased with the application of a weak longitudinal magnetic field.

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Magnetic field dependence of nuclear spin polarization as a criterion for the triplet‐Overhauser mechanism

The Journal of Chemical Physics ◽

10.1063/1.439727 ◽

1980 ◽

Vol 72 (8) ◽

pp. 4368-4375 ◽

Cited By ~ 1

Author(s):

Richard S. Hutton ◽

Heinz D. Roth ◽

Marcia L. Manion Schilling

Keyword(s):

Magnetic Field ◽

Spin Polarization ◽

Field Dependence ◽

Nuclear Spin ◽

Magnetic Field Dependence ◽

Nuclear Spin Polarization

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Injection of spin polarized electrons in InAs quantum dots

MRS Proceedings ◽

10.1557/proc-1208-o02-02 ◽

2009 ◽

Vol 1208 ◽

Author(s):

Andreas Russ ◽

Mesut Yasar ◽

Athos Petrou ◽

George Kioseoglou ◽

Connie Li ◽

...

Keyword(s):

Magnetic Field ◽

Quantum Dots ◽

Spin Injection ◽

Emission Spectra ◽

Exchange Interactions ◽

Electron Spin Polarization ◽

Polarized Electrons ◽

Inas Quantum Dots ◽

Spin Polarized ◽

Spin Led

AbstractWe present the results of an electrical injection study of spin polarized electrons from ferromagnetic Fe contacts into electronic shells of self-assembled InAs quantum dots (QDs) incorporated in GaAs/AlGaAs spin LED structures. The circular polarization of the emitted light was measured as function of current and magnetic field. The polarization of the EL spectra exhibits strong maxima at energies that do not coincide with the electroluminescence (EL) intensity peaks. The magnetic field dependence of the polarization maxima is consistent with spin injection from the ferromagnetic Fe contacts. The experimental results are compared with calculated emission spectra from multi-exciton complexes (N = 2 and N = 6) as function of electron spin polarization. The energies of the EL features as well as their polarization characteristics are understood in terms of energy shifts due to exchange interactions between spin-down electrons occupying adjacent shells.

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Tryptophan 13C nuclear-spin polarization generated by intraprotein electron transfer in a LOV2 domain of the blue-light receptor phototropin

Biochemical Society Transactions ◽

10.1042/bst0370382 ◽

2009 ◽

Vol 37 (2) ◽

pp. 382-386 ◽

Cited By ~ 18

Author(s):

Wolfgang Eisenreich ◽

Markus Fischer ◽

Werner Römisch-Margl ◽

Monika Joshi ◽

Gerald Richter ◽

...

Keyword(s):

Electron Transfer ◽

Spin Polarization ◽

Blue Light ◽

13C Nmr ◽

Nuclear Spin ◽

Nuclear Spin Polarization ◽

Blue Light Receptor ◽

Spin Polarized ◽

Light Receptor

13C-NMR experiments were performed on photo-excited fully and partially 13C-labelled LOV2 domains of the blue-light receptor phototropin. In the present paper, we report on nuclear-spin polarized tryptophan resonances that are generated by light-induced intraprotein electron transfer to the FMN cofactor. The spectra are discussed with respect to earlier data obtained from 13C-NMR experiments on unlabelled LOV2 domains that have been reconstituted with FMN 13C isotopologues.

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Photochemistry of Pivalaldehyde in Solution Studied by CIDNP

Canadian Journal of Chemistry ◽

10.1139/v73-452 ◽

1973 ◽

Vol 51 (18) ◽

pp. 3032-3038 ◽

Cited By ~ 3

Author(s):

Holger E. C. Chen ◽

Arend Groen ◽

Michael Cocivera

Keyword(s):

Free Radicals ◽

Spin Polarization ◽

Nuclear Spin ◽

The Other ◽

Radical Reactions ◽

Carbonyl Carbon ◽

Nuclear Spin Polarization ◽

Butyl Group ◽

Spin Polarized ◽

Tertiary Carbon

The n.m.r. spectrum observed during irradiation of pivalaldehyde dissolved in perfluoromethylcyclohexane indicates the formation of several compounds whose hydrogens are spin polarized. These compounds are 2-methylpropane, 2-methylpropene, and pivalaldehyde. A mechanism involving radical reactions which is consistent with these results is presented. According to this mechanism, the primary photochemical step is cleavage of the bond between the carbonyl carbon and the tertiary carbon of the t-butyl group. In contrast, this step does not appear to be important for acetaldehyde. As a test of the proposed mechanism CCl4 is added to trap free radicals. In this case, one of the products is CCl3COH. A mechanism for the formation of this and the other products having nuclear spin polarization is presented.

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