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In this paper, method of current images is used to calculate magnetic field of a rectangular loop in presence of high-permeability material. We provide closed form description for the images of the current loop placed between two semi-infinite blocks of high-permeability material, in the cases when the plane of the loop is parallel or perpendicular to the surfaces of blocks. A case study of using the method of images to calculate magnetic field of rectangular loop inside cube made of high-permeability material is also provided. [Projekat Ministarstva nauke Republike Srbije, br. TP32016]

Lorentz force eddy current testing (LET) is a novel nondestructive testing technique which can be applied preferably to the identification of internal defects in nonmagnetic moving conductors. The LET is compared (similar testing conditions) with the classical eddy current testing (ECT). Numerical FEM simulations have been performed to analyze the measurements as well as the identification of internal defects in nonmagnetic conductors. The results are compared with measurements to test the feasibility of defect identification. Finally, the use of LET measurements to estimate of the electrical conductors under test are described as well.

The induced electric field profiles in a homogeneous isotropic sphere, were calculated and compared between an analytic and a finite-element method in the framework of transcranial magnetic stimulation (TMS). This model can also be applied for concentric spheres in the framework of magnetic induction tomography (MIT), non destructive testing (NDT) or to calculate the lead field in magnetoencephalography (MEG). The calculations were performed using Eaton’s method as well as the finite-element program Comsol Multiphysics 4.2a (COMSOL Inc., Burlington, USA). A circular- and a figure-of-8 coil were used to operate as the sources of excitation. In our study the spherical volume conductor represents the human head consisting of grey matter. In order to quantify the differences between both methods an intense parameter study was performed. A comparison between both methods show a higher conformity than reported in previous studies. Regarding Eaton’s method, the influence of the maximum order of approximation L and the number of elements per winding K was investigated. The maximum relative difference was approximately 0.3% for L = 20 and K > 16. Furthermore the relative efficiency of the algorithm was calculated to save computational time. With the presented results it is possible to use Eaton’s method efficiently to compute the induced electric field profiles very quickly for example while searching for specific coil arrangements around the humans head, as in the case of deep brain transcranial magnetic stimulation (dTMS).

The performance result of a niobium photoswitch, realized on the ground plane layer of the low-Tc FLUXONICS RSFQ process which was designed, simulated and integrated with a processing RSFQ circuit is presented.

Research is described involving a tool for optimizing high temperature superconductor (HTS) logic circuits with large noise immunity.

Research is described involving parasitic interactions between the interconnects in high-density packaged RSFQ logic circuits.

Research describing the measurement of electromagnetic coupling in Josephson junction devices is presented. In particular the finite difference time domain technique is investigated.

Research is presented concerning the use of the Fokker-Planck equation in the calculation of the switching probability and bit error rates in a single Josephson junction, a comparator and a SQUID. Thermal noise analysis is discussed.

A hardware description language-based nominal circuit behavior modeling approach is proposed for the multipurpose design of rapid single flux quantum logic circuits. The approach provides circuit behavior evaluation criteria which can be employed in the input for circuit simulation as well as a yield-driven optimization cycle behavioral reference. The approach permits mixed-mode simulation and offers benefits in analysis speed-up and error localization.

The simplicial approximation and centers-of-gravity design centering methods were compared. They were applied to several rapid single flux quantum circuits and analytical test functions to test their effectiveness. Circuit simulation was conducted using a SPICE-type program with analog behavior modeling and transient noise simulation capabilities. An interactive yield optimization framework for cryoelectronic circuits was developed using the yield optimization strategies.