Abstract: A superconductor tape stack can have good current sharing characteristics and low contact resistivity. An electrically conductive material can be used to couple superconductor tapes to each other. In an embodiment, the superconductor tape stack can include double-sided superconductor tapes in a 2X configuration. In other embodiments, the superconductor tape stack can include single-sided superconductor tapes in a F2B configuration. One or more enhancements may be used to help reduce the contact resistivity. The enhancements can include slotted tapes, a conductive buffer layer stack, a relatively low resistivity substrate, a thinner substrate, a thicker stabilizer layer along sidewalls of the tapes, and combinations thereof. A superconductor tape may also have one or more of the enhancements described with respect to the superconductor tape stack. A magnetic coil can have a winding that includes the superconductor tape stack or the superconductor tape.

Abstract: A superconductor wire can achieve a Je of at least 600 A/mm2 at 4.2 K, 20 T applied magnetic field, which is greater than Je previously reported in the literature. The superconductor wire can include superconductor tape stands that have Ic per total strand width of at least 125 A/mm at 4.2 K, 20 T applied magnetic field. In an embodiment, the superconductor wire can have superconductor film with a modified REBCO composition, where (Ba+M)/Cu is at least 0.72. In the same or different embodiment, the superconductor film can have a thickness of at least 3 microns. The superconductor tape strands can have a stabilizer layer, where the thickness of the stabilizer is selected so that the neutral plane of the strands is near or passes through the superconductor film. A superconductor cable can be made from superconductor wires.