scholarly journals REBCO tape performance under high magnetic field

2017 ◽  
Vol 79 (3) ◽  
pp. 30601 ◽  
Author(s):  
Tara Benkel ◽  
Yasuyuki Miyoshi ◽  
Xavier Chaud ◽  
Arnaud Badel ◽  
Pascal Tixador
Keyword(s):  
Magnetic Field ◽  
High Magnetic Field ◽  
High Field ◽  
Low Cost ◽  
High Temperature Superconductors ◽  
Transverse Component ◽  
Experimental Results ◽  
Promising Candidate ◽  
Hts Magnet ◽  
Resistive Magnet

New improvements in high temperature superconductors (HTS) make them a promising candidate for building the next generation of high field magnets. As the conductors became recently available in long length, new projects such as NOUGAT (new magnet generation to generate Tesla at low cost) were started. This project aims at designing and building an HTS magnet prototype generating 10 T inside a 20 T resistive magnet. In this configuration, severe mechanical stress is applied on the insert and its extremities are subject to a high transverse component of the field. Because the conductor has anisotropic properties, it has to be studied carefully under similar conditions as the final prototype. First, this paper presents both the NOUGAT project and its context. Then, it shows the experimental results on short HTS tapes studied under high magnetic field up to 23 T with varying orientation. These results allow validating the current margin of the prototype. Finally, a first wound prototype is presented with experimental results up to 200 A under 16 T.

An application of high-temperature superconductors YBCO to magnetic separation

2017 ◽  
Vol 31 (25) ◽  
pp. 1745001 ◽  
Author(s):  
Qiudong Guo ◽  
Peng Zhang ◽  
Lin Bo ◽  
Guibin Zeng ◽  
Dengqian Li ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
Magnetic Separation ◽  
High Magnetic Field ◽  
Low Cost ◽  
Rapid Development ◽  
High Temperature Superconductors ◽  
New Approach ◽  
Industrial Areas ◽  
Ybco Tape

With the rapid development of manufacturing technology of high temperature superconductive YB[Formula: see text]Cu3O[Formula: see text] YBCO materials and decreasing in cost of production, YBCO is marching into industrial areas with its good performances as source of high-magnetic field and rather low cost in reaching superconductivity. Based on analysis of the performance of high temperature superconductors YBCO and development of technology in superconductive magnetic separation both home and abroad, we propose a new approach of taking YBCO tape to make a solenoid as the source of a high magnetic field of magnetic separatior of ores. The paper also looks into the future of the YBCO high temperature superconductive magnetic separation from the perspective of technology and cost, as well as its applications in other industries.

High-field liquid state NMR hyperpolarization: a combined DNP/NMRD approach

2014 ◽  
Vol 16 (35) ◽  
pp. 18781-18787 ◽  
Author(s):  
Petr Neugebauer ◽  
Jan G. Krummenacker ◽  
Vasyl P. Denysenkov ◽  
Christina Helmling ◽  
Claudio Luchinat ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Magnetic Field ◽  
Dynamic Nuclear Polarization ◽  
Liquid State ◽  
High Field ◽  
Nuclear Polarization ◽  
Nmr Relaxation ◽  
Relaxation Dispersion ◽  
Liquid Solutions ◽  
High Fields

Dynamic nuclear polarization and NMR relaxation dispersion measurements have been performed on liquid solutions of TEMPOL radicals in solvents with different viscosities at a high magnetic field of 9.2 T. The results indicate that fast dynamics significantly contribute to DNP enhancements at high fields.

MAGNETIC STUDIES OF SUPERCONDUCTING GdBa2Cu3O6+δ AT LOW TEMPERATURE AND HIGH FIELD

1987 ◽  
Vol 01 (05n06) ◽  
pp. 245-250 ◽  
Author(s):  
C.Y. HUANG ◽  
Y. SHAPIRA ◽  
P.H. HOR ◽  
R.L. MENG ◽  
C.W. CHU
Keyword(s):  
Magnetic Field ◽  
Low Temperature ◽  
High Magnetic Field ◽  
High Field ◽  
Paramagnetic Phase ◽  
Néel Temperature ◽  
Magnetic Studies ◽  
Spin Subsystem ◽  
Very High ◽  
Canted Phase

The magnetization of antiferromagnetic superconducting GdBa2Cu3O6+δ has been measured for ~1.5<T≤4.2 K for field up to ~20 T. We found that all Gd3+ spins are nearly parallel at very high field, and that this saturated spin subsystem coexists with superconductivity. Below the Néel temperature, 2.22 K, we observed the transition from the “canted” phase to the paramagnetic phase by the application of a high magnetic field.

scholarly journals Clear evidence against superconductivity in hydrides under high pressure

2021 ◽  
Author(s):  
Jorge Hirsch ◽  
Frank Marsiglio
Keyword(s):  
Magnetic Field ◽  
High Pressure ◽  
High Temperature ◽  
Magnetic Fields ◽  
Experimental Evidence ◽  
High Temperature Superconductors ◽  
Meissner Effect ◽  
Experimental Results ◽  
Definitive Evidence

Abstract The Meissner effect, magnetic field expulsion, is a hallmark of superconductivity. Associated with it, superconductors exclude applied magnetic fields. Recently Minkov et al. presented experimental results reportedly showing ``definitive evidence of the Meissner effect'' in sulfur hydride and lanthanum hydride under high pressure [1]. Instead, we show here that the evidence presented in that paper does not support the case for superconductivity in these materials. Together with experimental evidence discussed in earlier papers, we argue that this clearly indicates that hydrides under pressure are not high temperature superconductors.

A two-dimensional analysis of mode conversion at a resonance layer with high-magnetic field side reflection

2007 ◽  
Vol 73 (4) ◽  
pp. 473-484
Author(s):  
NORA NASSIRI-MOFAKHAM ◽  
AKBAR PARVAZIAN
Keyword(s):  
Magnetic Field ◽  
High Magnetic Field ◽  
High Field ◽  
Mode Conversion ◽  
Coupling Parameter ◽  
Local Heating ◽  
Current Drive ◽  
Planar Geometry ◽  
Two Dimensional ◽  
Additional Degree

AbstractMode converted Bernstein waves potentially allow the implementation of local heating and current drive in spherical torus devices, which are not directly accessible to low-harmonic cyclotron waves. The mode conversion method of Cairns and Lashmore-Davies previously used to study the usual mode conversion in non-planar geometry is extended to include the effect of the high-magnetic-field-side cutoff, and is solved analytically. The analytic solutions to the triplet, cutoff–resonance–cutoff, equations give the reflection and conversion coefficients in terms of parameters defining the local behavior of the dispersion relation. The variation of mode conversion efficiency depends not only on the coupling parameter but also on the phasing effect introduced by the high-field-side cutoff. The change in characteristic phases, which are concerned with the coupling parameter, brings an additional degree of freedom allowing optimization via the position of the high-field cutoff. A discrete spectrum of phases exists for which complete mode conversion of the incident wave for a transit of the resonance region can be achieved. The results we obtain here give the general conditions for efficient Bernstein wave heating in two-dimensional geometry.

The national high magnetic field laboratory: A new facility in support of high field research - DC facility in Tallhassee

1994 ◽  
Vol 201 ◽  
pp. 504-506 ◽  
Author(s):  
B.L. Brandt ◽  
J.E. Crow ◽  
H.J. Schneider-Muntau ◽  
D.M. Parkin ◽  
N.S. Sullivan
Keyword(s):  
Magnetic Field ◽  
High Magnetic Field ◽  
High Field ◽  
Field Research ◽  
Field Laboratory ◽  
New Facility

scholarly journals Physics design point of high-field stellarator reactors

2022 ◽  
Author(s):  
J Arturo Alonso ◽  
Ivan Calvo ◽  
Daniel Carralero ◽  
Jose Luis Velasco ◽  
José Manuel García Regaña ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
High Field ◽  
High Temperature Superconductors ◽  
Three Dimensional ◽  
Density Variation ◽  
Similar Degree ◽  
Design Point ◽  
Auxiliary Power ◽  
Fast Ion

Abstract The ongoing development of electromagnets based on High Temperature Superconductors has led to the conceptual exploration of high-magnetic-field fusion reactors of the tokamak type, operating at on-axis fields above 10 T. In this work we explore the consequences of the potential future availability of high-field three-dimensional electromagnets on the physics design point of a stellarator reactor. We find that, when an increase in the magnetic field strength $B$ is used to maximally reduce the device linear size $R\sim B^{-4/3}$ (with otherwise fixed magnetic geometry), the physics design point is largely independent of the chosen field strength/device size. A similar degree of optimization is to be imposed on the magnetohydrodynamic, transport and fast ion confinement properties of the magnetic configuration of that family of reactor design points. Additionally, we show that the family shares an invariant operation map of fusion power output as a function of the auxiliary power and relative density variation. The effects of magnetic field over-engineering and the $R(B)$ scaling of design points with constant neutron wall loading are also inspected. In this study we use geometric parameters characteristic of the \emph{helias} reactor, but most results apply to other stellarator configurations.

High Magnetic Field Studies of AlGaN/GaN Heterostructures Grown on Bulk GaN, SiC, and Sapphire Substrates

2000 ◽  
Vol 639 ◽  
Author(s):  
W. Knap ◽  
E. Borovitskaya ◽  
M. S. Shur ◽  
R. Gaska ◽  
G. Karczewski ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Magnetic Field ◽  
Cyclotron Resonance ◽  
Room Temperature ◽  
Field Studies ◽  
Experimental Results ◽  
Energy Structure ◽  
High Electron ◽  
Energy Gaps ◽  
Bulk Gan

ABSTRACTWe present the results of the high magnetic field studies of properties of two-dimensional electron gas (2DEG) in AlGaN/GaN heterostructures grown over high-pressure bulk GaN, sapphire, and insulating SiC substrates. The experimental results include the low field Hall measurements, cyclotron resonance measurements, and cryogenic temperature Quantum Hall Effect studies as well as room-temperature characteristics of High Electron Mobility Transistors fabricated on all these substrates. The room temperature high field measurements allow us to clearly separate the contributions of a parasitic parallel conduction from 2DEG conduction in all investigated heterostructures.The magnetotransport measurements are performed in the magnetic fields up to 30 Tesla for temperatures between 50mK-300K. This high magnetic field in combination with very high mobilities (over 60.000 cm2/Vs) in the sample on the bulk GaN substrates allow us to observe features related both to cyclotron resonance and spin splitting. The temperature dependence of this splitting determines the spin and cyclotron resonance energy gaps and, in combination with cyclotron resonance and tilted field experiments, allows us to determine the complete energy structure of 2DEG conduction band. We also present the first experimental results showing so called “the exchange enhancement” of the energy gaps between spin Landau levels.

scholarly journals Susceptibility weighted imaging at ultra high magnetic field strengths: Theoretical considerations and experimental results

2008 ◽  
Vol 60 (5) ◽  
pp. 1155-1168 ◽  
Author(s):  
Andreas Deistung ◽  
Alexander Rauscher ◽  
Jan Sedlacik ◽  
Jörg Stadler ◽  
Stephan Witoszynskyj ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Magnetic Field ◽  
Experimental Results ◽  
Susceptibility Weighted Imaging ◽  
Theoretical Considerations ◽  
Field Strengths

scholarly journals Clear evidence against superconductivity in hydrides under high pressure

2022 ◽  
Author(s):  
J. E. Hirsch ◽  
F. Marsiglio
Keyword(s):  
Magnetic Field ◽  
High Pressure ◽  
High Temperature ◽  
Magnetic Fields ◽  
Experimental Evidence ◽  
High Temperature Superconductors ◽  
Meissner Effect ◽  
Experimental Results ◽  
Definitive Evidence

Abstract The Meissner effect, magnetic field expulsion, is a hallmark of superconductivity. Associated with it, superconductors exclude applied magnetic fields. Recently Minkov et al. presented experimental results reportedly showing “definitive evidence of the Meissner effect” in sulfur hydride and lan-thanum hydride under high pressure1. Instead, we show here that the evidence presented in that paper does not support the case for superconductivity in these materials. Together with experimental evidence discussed in earlier papers, we argue that this clearly indicates that hydrides under pressure are not high temperature superconductors.

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