Finite element method analysis of the coupling effect between superconducting filaments of different aspect ratio

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This data are the raw files from the experiments with T-REX and the respective .m file to load, convert and plot them. This is currents, voltages, magnetic fields. Within the .zip files the raw data are contained among with the .m files to run, compile, calculate and create figures.

We report microwave spectroscopy of 167Er3+ doped in CaWO4, which reveals the hyperfine splitting of the erbium electronic ground state (Z1, Jeff = 15/2) induced by the I = 7/2 nuclear spin. From spectra measured below similar to 50 mK in magnetic fields up to 200 mT, we extract spin-Hamiltonian parameters including the electron g, hyperfine A, and nuclear electric quadrupolar Q tensors. Crucially, our analysis demonstrates unambiguously that the previously unobserved nuclear electric quadrupolar moment is

Context. The magnetic field has been shown to play a crucial role in star formation. Dust polarization is one of the most effective tools for probing the properties of the magnetic field, yet it does not directly trace its strength. To bridge this gap, several methods have been developed, combining polarization and spectroscopic data, to estimate the strength of the magnetic field. The most widely applied method was developed by Davis (1951, Phys. Rev., 81, 890) and Chandrasekhar & Fermi (1953, ApJ, 118, 11

The recent Far-Infrared Polarimetric Large-Area Central Molecular Zone Exploration (FIREPLACE) survey with SOFIA has mapped plane-of-sky magnetic field orientations within the Central Molecular Zone (CMZ) of the Milky Way. Applying the Histogram of Relative Orientations analysis to the FIREPLACE data, we find that the relative orientation between magnetic fields and column density structures is random in low-density regions ( 2x1022 less than or similar to NH2 less than or similar to 1023cm-2 ) but becomes

Earthing of electrical installations is mainly governed by safety rules. Electromagnetic compatibility also deals with earthing, among other circuit characteristics. Tokamaks are large-scale electrical installations that are known to generate large and low frequency magnetic fields as well as large and high frequency electric fields. Four European Tokamak installations have been investigated, from the earthing point of view, to identify appropriate techniques to earth the electrical equipment and to provide

Pyramidal, site-controlled InGaAs/AlGaAs quantum dots (QDs) are studied by micro-photoluminescence (PL) spectroscopy in a magnetic field. The light-hole (LH) excitonic transitions exhibit diamagnetic shifts similar to those of their heavy-hole (HH) counterparts. From the evolution of the excitonic lines, effective g-factors of g = 1.7 and 0.4 for HH and LH neutral excitons are inferred. (c) 2007 Elsevier B.V. All rights reserved.

We present an application of the conformal mapping (CM) method to determine the magnetic field and force in an electromechanical actuator. First, we show how to find, using a special type of CM known as the Schwarz-Christoffel mapping, the magnetic field in such a configuration. Then, we integrate the field in order to determine the force acting on the actuator moving part. The results are verified by a finite-element method.

The current repartition inside a HTS cable is very important for determining its AC losses and can be influenced by the uniformity of several parameters, either linked to the physical properties of the individual tapes (critical current Ic and power index n) or due to the manufacturing process (contact resistance). This work investigates the importance of the non-uniformity of these parameters for a manufactured 16-tape straight superconducting cable by means of finite element method (FEM) simulations. The

In typical power applications, Bi-2223 conductors carrying ac current will be subjected to external magnetic fields, whose orientation and conductor’s geometry are of major significance for the ac loss magnitude. This paper investigates the influence of the geometry and aspect ratio of non-twisted Bi-2223 conductors in reducing the ac loss for such applications. A numerical model of high-Tc materials has been used in finite-element-method simulations. The model incorporates power-law E-J characteristics wit

The aim of this work is to determine the existence and degree of the current unbalance of two types of Cable-In-Conduit Conductors (CICC) of the SeCRETS long sample experiment, and its influence on the conductors' performance. The self-field,measurements are performed by using six sets of annular Hall sensors, each containing six sensors, and two linear arrays with ten sensors. The change of the self-field is associated with the redistribution of the transport current between the strands inside the conducto

The linear equation for ideal magnetohydrodynamic ballooning modes in three-dimensional configurations is derived in the coordinate system that is optimal for the representation of the equilibrium state. The magnetic field lines in this coordinate system, however, are not straight. The form of the Mercier criterion that is currently in use is recovered from the asymptotic analysis of the ballooning equation. To determine the parallel-current density, a magnetic differential equation expressed in the optimal

An electronic compass made of a new planar 2D micro-fluxgate sensor is presented. The magnetometer is integrated in a standard CMOS process, and uses a post-processed cross shape ferromagnetic amorphous core. This core is diagonally placed above a single square excitation coil common to both measurement axes. The silicon chip includes the driving and readout electronics, the excitation and pick-up coils made of the two CMOS process metallization layers. The ferromagnetic core is integrated from commercially

The conceptual design of the large gap Spectrometer Dipole for the LHC-b experiment is presented here. The required acceptance implies a gap height of 3.6 m and a width of 4.3 m. Although the magnetic induction of the 1.92 m long magnet is only 1.1 T, it turns out that a superconducting (SC) coil is the most economic solution. The design considerations for the yoke and the SC-coil are explained, the parameters of the conductor, coil, cooling system are presented and the quench behavior is estimated.

This work deals with the modelling of electrochemical reactors with bipolar electrodes. We give a numerical model which enables us to compute electrical current and potential distributions in an electrochemical cell of any type of geometry in two and three dimensions, including electrodes at an unknown floating potential. We first present electrochemical reactors and particularly insist on kinetics and thermodynamics phenomena responsible on potential discontinuities at electrodes-electrolyte interfaces. Se

In this Thesis we study several aspects of potential scattering in non-relativistic quantum mechanics. In the first part, we study the concept of time delay. More precisely, after an elementary introduction to the theory (chapter I), we clarify in chapter II the role played by the localizing regions in the definition of global time delay. In chapter III, we generalize the concept to arbitrary conditions of observation for the scattered particle (conditional time delay). In chapters IV and V, we address the

The surface impedance of type-II superconductors in the mixed state has been studied, taking into account the vortex elasticity and nonlocality (long-range interaction of vortices). An electromagnetic wave penetrates into a superconductor as a superposition of two exponentially decaying modes with different penetration lengths, in contrast with one mode in a normal conductor or in a superconductor in the Meissner state. The second mode is an elastic mode of the vortex array; it is crucial for incorporation

We have studied electronic properties of (YBa2Cu3O6.9)1-xAgx compounds with 5, 10, 15, 25 and 50 wt% Ag. In our samples, the silver fills the intergranular space and the superconductivity is preserved even at 50 wt% Ag(Tc=87 K). These samples can be safely dropped in water without loss of superconductivity. The magnitude of electrical resistivity at 300 K rapidly decreases from 103 μΩcm for 5 wt% Ag down to approximately 30 μΩcm for 50 wt% Ag. The superconducting transition is always around 92 K. Preliminar

Finite element method analysis of the coupling effect between superconducting filaments of different aspect ratio

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