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2018). Two level undercut-profile substrate-based filamentary coated conductors produced using metal organic chemical vapor deposition. I E E E Transactions on Applied Superconductivity, 28(4), [6601705]. https://doi.Abstract-The two level undercut-profile substrate (2LUPS) has been introduced as a concept for subdividing rare-earth-Ba2Cu3O7 coated conductors (CC) into narrow filaments that effectively reduces the AC losses and improves field stability for DC magnets. The 2LUPS consists of two levels of plateaus connected by a wall with an undercut-profile, which enables a physical separation of the superconducting layer between the plateaus without reducing the effective width of the superconducting layer.In this study we report for the first time the results of fabrication and characterization of a filamentary CC produced in an industrial setup by SuperPower Inc. using ion beam assisted deposition and metal organic chemical vapor deposition (IBAD-MOCVD) on a 2LUPS realized at the Technical University of Denmark (DTU), whereas previous studies discussed the fabrication using alternating beam assisted deposition and pulsed laser deposition (ABAD-PLD).We also present Hall probe scanning measurements performed using a standard THEVA TAPESTAR™ XL machine that is routinely employed for industrial critical current characterization of long length CCs. From these results is it clear that additional analysis of the measured field profiles are required when characterizing filamentary 2LUPS CC using a standard TAPESTAR™ setting. Using a model representation of the 2LUPS we calculated the expected magnetization response by means of finite element methods simulations and we find a good agreement with the experimentally observed magnetic profiles.  Index Terms-Multifilamentary superconductors, Hightemperature superconductors, Magnetic variables measurement, Finite element analysis.

We have studied fluctuations on the electrical conductivity in granular Tm 1-x Pr x Ba 2 Cu 3 O 7-δ (0 ≤ x ≤ 0.10) superconductors. Samples were prepared by the standard solid-state reaction technique. The results are described in terms of the temperature derivative of the resistivity, dρ/dT, and of the logarithmic temperature derivative of the conductivity, d ln (Δσ)/dT. The results show clearly that the resistive transition proceeds in two stages: intragranular and intergranular. Also, it was not observed in dρ/dT, near the transition, a structure consisting of two closely separated maxima, as seen in studies with other rare earth elements. Yet, the analysis of the conductivity in the normal phase has shown contributions from critical fluctuations and they were not affected by Pr doping. Below TC, on approaching the zero resistance state, our results show a power-law behavior with critical exponent s ≅ 4.1 for x = 0.00 and s ≅ 2.8 for x = 0.05 sample, indicating a phase transition from a paracoherent to a coherent state of the granular array. This behavior was not observed for x = 0.10 sample, showing that Pr affected the coherence transition.

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