摘要:
The various embodiments described herein include methods, devices, and systems for fabricating and operating superconducting circuits. In one aspect, an electric circuit includes: (1) a first superconducting component having a first terminal, a second terminal, and a constriction region between the first terminal and the second terminal; (2) a second superconducting component having a third terminal and a fourth terminal; and (3) a first electrically-insulating component that thermally couples the first superconducting component and the second superconducting component such that heat produced at the constriction region is transferred through the first component to the second superconducting component.
摘要:
In various embodiments, superconducting wires incorporate diffusion barriers composed of Ta alloys that resist internal diffusion and provide superior mechanical strength to the wires.
摘要:
A new heat treatment for Internal-Tin Nb3Sn strands is described. The heat treatment uses Nausite membranes to decrease the volume fraction of the η phase and therefore minimize its liquefaction—ultimately resulting in better connected Nb3Sn. The heat treatment requires only one stage aside from the final Nb3Sn reaction stage. This heat treatment enables an increase in critical current density (at 16 T) of 28%.
摘要:
Examples described in this disclosure relate to a memory cell having a magnetic Josephson junction device with a doped magnetic layer. In one example, a memory cell including a magnetic Josephson junction (MJJ) device is provided. The MJJ device may include at least a first layer formed above a second layer and a third layer formed below the second layer, where the first layer is a free magnetic layer, the second layer is a non-magnetic layer, where the third layer is a fixed magnetic layer. The free magnetic layer may comprise a magnetic alloy doped with at least one of Vanadium, Zirconium, Molybdenum, or Hafnium, and the fixed magnetic layer may comprise an un-doped second magnetic alloy.
摘要:
This disclosure will describe a novel finding and make the claim for the first time on a group of old compounds and formulated new compounds. These compounds have superconducting property at high temperatures, i.e., 151K or higher. Several compounds were prepared, though not well-purified, at around middle of 1900s. Their chemical, structural, electric and magnetic properties were studied and reported but their superconducting property has not been known and has never been exploited because the idea of type-II superconductivity was not proposed at that time. Consequently, we claim this finding as an invention even though our invention is based on the studies of the compounds' electric and magnetic properties along with their crystallographic features from the previous publications. The experiments to further verify their high temperature superconductivity require the utilization of sophisticated facilities on synthesizing highly pure compounds and the deregulation from government security authorities on purchasing the starting materials.
摘要:
An improved microfabrication technique for Josephson junctions in superconducting integrated circuits, based on the use of a double-layer lithographic mask for partial anodization of the side-walls and base electrode of the junctions. The top layer of the mask is a resist material, and the bottom layer is a dielectric material chosen so to maximize adhesion between the resist and the underlying superconducting layer, be etch-compatible with the underlying superconducting layer, and be insoluble in the resist and anodization processing chemistries. The superconductor is preferably niobium, under a silicon dioxide layer, with a conventional photoresist or electron-beam resist as the top layer. This combination results in a substantial increase in the fabrication yield of high-density superconducting integrated circuits, increase in junction uniformity and reduction in defect density. A dry etch more compatible with microlithography may be employed.
摘要:
An apparatus includes a base layer; and a superconducting nanowire disposed on the base layer in a continuous meander pattern and including an amorphous metal-metalloid alloy such that the apparatus is configured to detect single photons, and the continuous meander pattern includes: a plurality of parallel line segments; and a plurality of curved segments, wherein adjacent parallel line segments are joined by a curved segment. A method for making an apparatus for detecting single photons includes forming a base layer; forming a superconducting layer on the base layer; patterning the superconducting layer; and forming a continuous meander pattern from the superconducting layer, the continuous meander pattern includes a plurality of parallel line segments; and a plurality of curved segments, wherein adjacent parallel line segments are joined by a curved segment; and forming a dielectric layer on the continuous meander pattern, the dielectric layer including a dielectric material that is substantially transparent to a predetermined photon wavelength, wherein the apparatus is configured to detect single photons.
摘要:
A magnetic topological nanowire structure comprises a superconductor and a quasi-1D magnetic nanowire. The quasi-1D magnetic nanowire is coupled to or embedded in the superconductor to produce a self-contained interaction resulting in a spatially separated pair of Majorana fermions. The pair of Majorana fermions corresponds to the topological superconductor and each of the pair of the Majorana fermions are localized near a respective endpoint of the nanowire.
摘要:
A high-temperature superconducting film includes a SrTiO3 substrate, a single crystalline FeSe layer, and a protective layer with a layered crystal structure. The single crystalline FeSe layer is sandwiched between the SrTiO3 substrate and the protective layer via a layer-by-layer mode. An onset temperature of superconducting transition of the high-temperature superconducting film is greater than or equal to 54 K, and a critical current density of the high-temperature superconducting film is about 106 A/cm2 at 12 K.
摘要:
An objective of the present invention is to provide a copper substrate for epitaxial growth, which has higher biaxial crystal orientation, and a method for manufacturing the same. The substrate for epitaxial growth of the present invention contains a biaxially crystal-oriented copper layer, wherein the full width at half maximum Δφ of a peak based on the pole figure of the copper layer is within 5° and the tail width Δβ of the peak based on the pole figure is within 15° Such a substrate for epitaxial growth is manufactured by a 1st step of performing heat treatment of a copper layer so that Δφ is within 6° and the tail width Δβ is within 25°, and after the 1st step, a 2nd step of performing heat treatment of the copper layer at a temperature higher than the temperature for heat treatment in the 1st step, so that Δφ is within 5° and the tail width Δβ is within 15°.