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The screening current induced in superconductors can passively shield external magnetic fields and hence provide a noise free environment for precision sensors and instruments. This paper presents a novel design employing artificial joint-free REBCO (REBa2Cu3O7-x, RE: rare earths) coils which can economically extend the field shielding space for larger instruments, e.g. clinical equipment. We compared the shielding factors of single, double and multi-coils, and confirmed a coil with Helmholtz construction as the optimal architecture. Due to the zero resistance of the joint-free REBCO coils, the shielding effectiveness reaches 80 dB at the center of coils, shielding 99.99% of the external magnetic field of 10 μT at 1 × 10−5 Hz, and 40 dB (99%) in a greater spherical space of 40 mm in diameter. Additionally, the shielding effectiveness does not decrease in the external magnetic field of 1 nT. Such a low frequency magnetic shielding effect implies promising applications for the present work, such as preventing interference magnetic fields from precision instruments, which generally require field sensitivity as low as the fT · Hz−1/2 range. [ABSTRACT FROM AUTHOR]

LaMnO3−δ (LMO) films with different oxygen contents are deposited on Epi-MgO/IBAD-MgO templates using reactive magnetron sputtering under varying temperatures and atmospheres. Subsequent YBa2Cu3O7−δ (YBCO) films are grown on LMO layers by metal-organic deposition (MOD) method. X-ray diffraction measurements reveal that YBCO texture cannot be further improved when the full width at half maximum (FWHM) values of LMO (011) φ-scans (evaluation on in-plane alignment) and LMO (002) ω-scans (evaluation on out-of-plane alignment) for LMO films are less than 8° and 4°, respectively. Sharp orientation with in-plane FWHM value of <3° for YBCO (103) φ-scan and out-of-plane FWHM value of <1.5° for YBCO (006) ω-scan can typically be achieved in YBCO films. Precise control of growth conditions, especially atmosphere, remains a feasible way to modify the surface of LMO films. It induces changes in oxygen content, lattice structure and surface morphology of LMO, and further affects the epitaxial growth of superconducting layers. Oxygen-deficient LMO with expanded lattice parameters and flat surface can effectively suppress the non-c-axis oriented YBCO, thereby enhancing the current carrying capability. The 500 m long YBCO coated conductors with conditioned LMO layers have an inductive critical current (Ic) ranging from 358 to 437 A/12 mm width with an average value of 398 A/12 mm width. [ABSTRACT FROM AUTHOR]

It is demonstrated that electrodeposition is a promising cost-effective technique to grow oxide buffer on metallic tapes. The resultant layer of CeO2 shows the biaxial texture of FWHM = 5.5° as well as a smooth surface of RMS = 2.0 nm, and YBa2Cu3O7−δ coated conductor with such a buffer exhibits the critical current density of 1.85 MA cm−2 at 77 K. Of more interest is that the CeO2 film thickness reaches a high value of more than 200 nm without any cracks, while it is very hard to achieve a thickness of more than 70 nm in the conventional vapor deposition methods employed. [ABSTRACT FROM AUTHOR]