A Josephson parametric converter is provided. The Josephson parametric converter includes a multi-Josephson junction ring modulator having arrays of N Josephson junctions arranged in a ring configuration with ring nodes inter-dispersed between the arrays. The multi-Josephson junction ring modulator further has a center node inter-connecting the ring nodes. N is an integer having a value greater than one. The Josephson parametric also includes a first and a second resonator formed from lumped-element capacitors that shunt the multi-Josephson junction ring modulator and respectively enable a first and a second mode of the Josephson parametric converter.

A Josephson parametric converter is provided. The Josephson, parametric convener includes a multi-Josephson junction ring modulator having arrays of N Josephson junctions arranged in a ring configuration with nodes inter-dispersed between the arrays. N is an integer having a value greater than one. The Josephson parametric converter further includes a first and a second resonator formed from lumped-element capacitors that shunt the multi-Josephson junction ring modulator and respectively enable a first and a second mode of the Josephson parametric converter. The Josephson parametric converter also includes a first and a second LC circuit for respectively coupling the first and the second resonator to external feedlines.

A fiber optical superconducting nanowire detector with increased detector efficiency, fabricated directly on the tip of the input optical fiber. The fabrication on the tip of the fiber allows precise alignment of the detector to the fiber core, where the field mode is maximal. This construction maximizes the coupling efficiency to close to unity, without the need for complex alignment procedures, such as the need to align the input fiber with a previously fabricated device. The device includes a high-Q optical cavity, such that any photon entering the device will be reflected to and fro within the cavity numerous times, thereby increasing its chances of absorption by the nanowire structure. This is achieved by using dedicated cavity mirrors with very high reflectivity, with the meander nanowire structure contained within the cavity between the end mirrors, such that photons impinge on the nanowire structure with every traverse of the cavity.

A BÏ2212 article may be formed by mixing metallic precursor powders including bismuth, strontium, calcium and copper in an oxygen-free atmosphere, mechanically alloying the metallic precursor powders in an oxygen-free atmosphere, and heating the metallic precursor alloy according to a temperature profile. The profile may include a ramp-up stage during which the alloy is heated to a peak temperature in an oxygen-free atmosphere, a dwell stage during which the alloy is held at the peak temperature for a dwell time, and a ramp-down stage during which the alloy is cooled from the peak temperature. During at least a portion of the dwell stage, the oxygen-free atmosphere is switched to an oxygen-inclusive atmosphere, wherein the alloy is oxidized to form a superconducting oxide, which may be sintered during or after oxidation. The alloy may be formed into a shape, such as a wire, prior to oxidizing.

The present invention relates to a precursor (1) for production of a high-temperature superconductor (HTS) in ribbon form, comprising a metallic substrate (10) in ribbon form having a first ribbon side (11) and a second ribbon side (12), wherein, on the first ribbon side (11), (a) the substrate (10) has a defined texture as template for crystallographically aligned growth of a buffer layer or an HTS layer and (b) an exposed surface of the substrate (10) is present or one or more layers (20,30) are present that are selected from the group consisting of: buffer precursor layer, pyrolyzed buffer precursor layer, buffer layer, HTS precursor layer, pyrolyzed HTS buffer precursor layer and pyrolyzed and further consolidated HTS buffer precursor layer, and, on the second ribbon side (12), at least one ceramic barrier layer (40) that protects the substrate (10) against oxidation or a precursor which is converted to such a layer during the HTS crystallization annealing or the pyrolysis is present, wherein, when one or more layers (20, 30) are present on the first ribbon side (11), the ceramic barrier layer (40) or the precursor thereof has a different chemical composition and/or a different texture than the layer (20) arranged on the first ribbon side (11) and directly adjoining the substrate (10). In this precursor, the barrier layer (40) is a layer that delays or prevents ingress of oxygen to the second ribbon side (12) and is composed of conductive ceramic material or a precursor which is converted to such a precursor during the HTS crystallization annealing or the pyrolysis, and the ceramic material is an electrically conductive metal oxide or an electrically conductive mixture of metal oxides, wherein the conductive metal oxide or one or more metal oxides in the conductive mixture is/are preferably metal oxide(s) doped with an extraneous metal.

Superconducting cables employ one or more superconducting tapes wound around a former. A compact superconducting cable is configured using a former having a small diameter, e.g., less than 10 millimeters. A flexible superconducting cable is configured with a former made of a flexible material. Superconducting tape conductors are wound around the former, with the superconducting layer in compression on the inside of the wind turns of the wind, to prevent irreversible damage to the superconductor. A layer of solder is on the superconducting tape(s) or solder sheaths are wound between tape conductors in each layer. The one or more solder layers or sheaths are melted to cause the solder to flow within the structure, to bond some or all of the superconducting tape conductors together and form a mechanically strong cable with an enhanced level of electrical connectivity between tapes in the cable.

Various techniques and apparatus permit fabrication of superconductive circuits. A niobium/aluminum oxide/niobium trilayer may be formed and individual Josephson Junctions (JJs) formed. A protective cap may protect a JJ during fabrication. A hybrid dielectric may be formed. A superconductive integrated circuit may be formed using a subtractive patterning and/or additive patterning. A superconducting metal layer may be deposited by electroplating and/or polished by chemical-mechanical planarization. The thickness of an inner layer dielectric may be controlled by a deposition process. A substrate may include a base of silicon and top layer including aluminum oxide. Depositing of superconducting metal layer may be stopped or paused to allow cooling before completion. Multiple layers may be aligned by patterning an alignment marker in a superconducting metal layer.

A superconducting power transmission system that comprises an inner pipe housing a superconducting cable therein, a radiation covering at least a part of the inner pipe from outside; and an outer pipe housing the inner pipe and the radiation shield therein. A vacuum is created in a space from an inside of the outer pipe to an outside of the inner pipe with the radiation shield therebetween. The system further comprises at least one radiation shield pipe, housed in the outer pipe and thermally coupled with the radiation shield, a liquefied natural gas (LNG) as a second cryogen for the radiation shield being made to flow through the radiation shield pipe.

A semiconductor device of an embodiment includes a layered substance formed by laminating two-dimensional substances in two or more layers. The layered substance includes at least either one of a p-type region having a first intercalation substance between layers of the layered substance and an n-type region having a second intercalation substance between layers of the layered substance. The layered substance includes a conductive region that is adjacent to at least either one of the p-type region and the n-type region. The conductive region includes neither the first intercalation substance nor the second intercalation substance. A sealing member is formed on the conductive region, or on the conductive region and an end of the layered substance.

A method of an embodiment includes forming a capacitor pad for a nonlinear resonator. In an embodiment, the method includes comparing a resonance frequency of the nonlinear resonator to a target frequency to determine whether the resonance frequency falls within a range of the target frequency. A device of an embodiment includes a first capacitor pad comprising a superconducting material, the first capacitor pad configured to couple to a first end of a logic circuit element. In an embodiment, the device includes a second capacitor pad comprising a second superconducting material, the capacitor pad configured to couple to a second end of the logic circuit element. In an embodiment, the second capacitor pad includes a first portion; a second portion; and a bridge configured to electrically connect the first portion and the second portion.