In various embodiments, superconducting wires incorporate diffusion barriers composed of Nb alloys or Nb—Ta alloys that resist internal diffusion and provide superior mechanical strength to the wires.

Methods of forming semiconductor-superconductor hybrid devices with a horizontally-confined channel are described. An example method includes forming a first isolated semiconductor heterostructure and a second isolated semiconductor heterostructure. The method further includes forming a left gate adjacent to a first side of each of the first isolated semiconductor heterostructure and the second isolated semiconductor heterostructure. The method further includes forming a right gate adjacent to a second side, opposite to the first side, of each of the first isolated semiconductor heterostructure and the second isolated semiconductor heterostructure, where a top surface of each of the left gate and the right gate is offset vertically from a selected surface of each of the first isolated semiconductor heterostructure and the second isolated semiconductor heterostructure by a predetermined offset amount. The method further includes forming a superconducting layer over each of the first isolated semiconductor heterostructure and the second isolated semiconductor heterostructure.

In various embodiments, superconducting wires incorporate diffusion barriers composed of Nb alloys or NbTa alloys that resist internal diffusion and provide superior mechanical strength to the wires.

In various embodiments, superconducting wires incorporate diffusion barriers composed of Nb alloys or NbTa alloys that resist internal diffusion and provide superior mechanical strength to the wires.

In various embodiments, superconducting wires incorporate diffusion barriers composed of Ta alloys that resist internal diffusion and provide superior mechanical strength to the wires.

In various embodiments, superconducting wires feature assemblies of clad composite filaments and/or stabilized composite filaments embedded within a wire matrix. The wires may include one or more stabilizing elements for improved mechanical properties.

A new heat treatment for Internal-Tin Nb.sub.3Sn strands is described. The heat treatment uses Nausite membranes to decrease the volume fraction of the phase and therefore minimize its liquefactionultimately resulting in better connected Nb.sub.3Sn. The heat treatment requires only one stage aside from the final Nb.sub.3Sn reaction stage. This heat treatment enables an increase in critical current density (at 16 T) of 28%.

A system and method for treating a cavity comprises arranging a niobium structure in a coating chamber, the coating chamber being arranged inside a furnace, coating the niobium structure with tin thereby forming an Nb.sub.3Sn layer on the niobium structure, and doping the Nb.sub.3Sn layer with nitrogen, thereby forming a nitrogen doped Nb.sub.3Sn layer on the niobium structure.

In various embodiments, superconducting wires incorporate diffusion barriers composed of Ta alloys that resist internal diffusion and provide superior mechanical strength to the wires.

A method for manufacturing a superconductor is described. A metal assembly precursor can be formed within a hollow copper support element. Forming the metal assembly precursor within a hollow copper support element by positioning a plurality of conductor elements about a core including Sn to provide a first plurality of inner interstitial spaces between the plurality of conductor elements between the core and conductor elements and a second plurality of outer interstitial spaces between the hollow copper support element and the core, the plurality of conductor elements including unreacted Nb. The metal assembly precursor can be reduced via cold drawing to produce a reduced metal assembly. The reduced metal assembly can be reaction heat treated so that the unreacted Nb undergoes a phase transformation to a reacted superconductor.