Magnetic properties of GaAs/Fe core/shell nanowires

Pimpinella, R. E.; Zhang, D.; McCartney, Martha R.; Smith, David J.; Krycka, Kathryn; Kirby, Brian J.; O'Dowd, B. J.; Sonderhouse, Lindsay; Leiner, J. C.; Liu, X.; Dobrowolska, M.; Furdyna, J. K.

doi:10.1063/1.4799252

Cited by 8 publications

(8 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At the NCNR, several recent studies have focused on understanding the structure of magnetic nanoparticles (Hasz et al , 2014; Krycka et al , 2014, 2009, 2010, 2013, 2011). SANS with NSFs has also been employed to study multiferroics (Ramazanoglu et al , 2011; Ueland et al , 2010), magnetostriction (Laver et al , 2010a), exchange-bias (Dufour et al , 2011), and nanowires (Pimpinella et al , 2013). Polarization analysis also allows for separation of coherent from spin-incoherent scattering (Moon et al , 1969; Williams, 1988), which is relevant to biological samples due to the substantial spin-incoherent scattering from hydrogen.…”

Section: Neutron Spin-filtersmentioning

confidence: 99%

Optically polarizedHe3

et al. 2017

View full text Add to dashboard Cite

This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements.

show abstract

Section: Neutron Spin-filtersmentioning

confidence: 99%

Optically polarizedHe3

et al. 2017

View full text Add to dashboard Cite

show abstract

“…At the NCNR, several recent studies have focused on understanding the structure of magnetic nanoparticles (Hasz et al, 2014;Krycka et al, 2014Krycka et al, , 2009Krycka et al, , 2010Krycka et al, , 2013Krycka et al, , 2011. SANS with NSFs has also been employed to study multiferroics (Ramazanoglu et al, 2011;Ueland et al, 2010), magnetostriction (Laver et al, 2010a), exchangebias (Dufour et al, 2011), and nanowires (Pimpinella et al, 2013). Polarization analysis also allows for separation of coherent from spin-incoherent scattering (Moon et al, 1969;Williams, 1988), which is relevant to biological samples due to the substantial spin-incoherent scattering from hydrogen.…”

Section: Brief Summary Of Neutron Scattering Physics Enabledmentioning

confidence: 99%

Optically Polarized $^3$He

Gentile,

Nacher,

Saam

et al. 2016

Preprint

View full text Add to dashboard Cite

This article reviews the physics and technology of producing large quantities of highly spin-polarized 3 He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3 He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements.

show abstract

“…In 2007 a program [49] to provide neutron spin filters for user experiments at the NCNR began and currently over 110 experiments conducted over 350 days of beam time have been supported. The primary applications have been small angle neutron scattering [50,51,52,53,54,55,56,57,58,59,60,61], triple-axis spectrometry [62,63,64,65,66,67], and polarized neutron reflectometry. In general these experiments are conducted with 3 He cells that are polarized off-line, transported to the neutron beam line in battery-operated solenoids, and stored on the beam line in compact, magnetically shielded solenoids or other magnetic field apparatus [49,68].…”

Section: Neutron Scatteringmentioning

confidence: 99%

Polarized 3He spin filters for neutron science

Gentile¹

2014

Proceedings of XVth International Workshop on Polarized Sources, Targets, and Polarimetry — PoS(PSTP2013)

View full text Add to dashboard Cite

The large spin dependence of the absorption cross section for neutrons by 3 He gas provides a method to polarize neutron beams. For certain applications, such polarized 3 He-based neutron "spin filters" have advantages over conventional neutron optical polarizing methods. Spin filters operate at all neutron wavelengths, can cover a large angular range and/or a large energy range, and decouple neutron polarization from energy selection. Both spin-exchange optical pumping (SEOP) and metastability-exchange optical pumping (MEOP) are currently being employed to polarize 3 He spin filters at various neutron facilities worldwide. We focus on the development and application of SEOP-based neutron spin filters at the National Institute of Standards and Technology (NIST), Center for Neutron Research (NCNR). The combination of long relaxation time spin filter cells, high power spectrally narrowed diode lasers, and the use of Rb/K mixtures have allowed us to reach 3 He polarizations up to 85 % in spin filter cells ≈1 liter in volume. Studies have revealed limits to the achievable polarization from temperature-dependent relaxation and unexplained magnetic field dependence for relaxation in SEOP cells. Applications include neutron scattering methods such as triple-axis spectrometry and small angle neutron scattering, and fundamental neutron physics. In most neutron scattering applications, cells are transported to the beam line and stored in a magnetically shielded solenoid or box. A recent focus has been apparatus for wide-angle neutron polarization analysis. A measurement of the spin-dependence of the neutron-3 He scattering length was performed with a small, polarized 3 He cell located inside a neutron interferometer. A precision measurement of the neutron polarization for this experiment was also performed with a 3 He spin filter. Use of spin filters in high flux neutron beams have revealed beam-induced alkali-metal relaxation and long term effects on SEOP spin filter cells.

show abstract

Magnetic properties of GaAs/Fe core/shell nanowires

Cited by 8 publications

References 7 publications

Optically polarizedHe3

Optically polarizedHe3

Optically Polarized $^3$He

Polarized 3He spin filters for neutron science

Contact Info

Product

Resources

About