A device including a semiconductor layer comprising first regions delimited by second regions and third regions; first electrostatic control gates including first conductive portions extending parallel to each other, in vertical alignment with the second regions; second electrostatic control gates including second conductive portions extending parallel to each other, in vertical alignment with the third regions; wherein each first gate includes an electrostatic control voltage adjustment element forming two impedances connected in series, one end of one of the impedances being coupled to the first conductive portion of the first gate and one end of the other of the impedances being coupled to a third conductive portion applying an adjustment electric potential to the second impedance, and wherein the value of at least one of the impedances is adjustable.

A superconducting device which includes a substrate, multiple niobium leads formed on the substrate, a niobium silicide (NbSi.sub.x) passivation layer formed on a surface of at least one of the multiple niobium leads, and an aluminum lead formed directly on at least a portion of the NbSi.sub.x passivation layer such that an interface therebetween is substantially free of oxygen and oxidized material, where the multiple niobium leads and the aluminum lead are constructed to carry a supercurrent while in use.

A method of fabricating a semiconductor-superconductor hybrid device comprises providing a workpiece comprising a semiconductor component, a layer of a first superconductor material on the semiconductor component, and a layer of a second superconductor material on the first superconductor material, the second superconductor material being different from the first superconductor material; etching the layer of the second superconductor material to expose a portion of the first superconductor material; and oxidising the portion of the first superconductor material to form a passivating layer on the semiconductor. The first superconductor provides energy coupling between the semiconductor and the second superconductor, and the passivating layer protects the semiconductor while allowing electrostatic access thereto. Also provided are a hybrid device, and a method of etching.

Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a substrate and a quantum well stack disposed on the substrate. The quantum well stack may include a quantum well layer and a back gate, and the back gate may be disposed between the quantum well layer and the substrate.

A product includes an array of cold spray-formed structures. Each of the structures is characterized by having a defined feature size in at least one dimension of less than 100 microns as measured in a plane of deposition of the structure, at least 90% of a theoretical density of a raw material from which the structure is formed, and essentially the same functional properties as the raw material. A product includes a cold spray-formed structure characterized by having a defined feature size in at least one dimension of less than 100 microns as measured in a plane of deposition of the structure, at least 90% of a theoretical density of a raw material from which the structure is formed, and essentially the same functional properties as the raw material.

Exemplary methods of fabricating high quality quantum computing components are described. The methods include removing native oxide from a deposition surface of a silicon substrate in a cleaning chamber of a processing system, and transferring the silicon substrate under vacuum to a deposition chamber of the processing system. The methods further include depositing an aluminum layer on the deposition surface of the silicon substrate in the deposition chamber, where an interface between the aluminum layer and the deposition surface of the silicon substrate is oxygen free.

One example includes a superconducting circuit. The circuit includes superconducting circuitry fabricated in a circuit layer. The circuit layer includes a first surface and a second surface opposite the first surface. The circuit also includes a flux moat comprising a dielectric material formed in the circuit layer. The flux moat can be configured to trap a magnetic flux as the superconducting circuit is cooled to below a superconducting critical temperature. The circuit further includes a magnetic film arranged proximal to the flux moat on at least one of the first and second surfaces of the circuit layer. The magnetic film can be configured to guide the magnetic flux to the flux moat as the superconducting circuit is cooled to below the superconducting critical temperature.

A superconducting device that mixes surface acoustic waves and microwave signals and techniques for fabricating the same are provided. A superconducting device can comprise a superconducting surface acoustic wave resonator and a superconducting microwave resonator. The superconducting device can also comprise a Josephson ring modulator coupled to the superconducting surface acoustic wave resonator and the superconducting microwave resonator. The Josephson ring modulator can be a dispersive nonlinear three-wave mixing element.

Techniques that can facilitate high-transparency semiconductor-metal interfaces are provided. In one example, a method can comprise forming a silicon on insulator (SOI) over a wafer. The method can further comprise depositing a metal on the SOI. The method can further comprise forming a structure by dry-etching the metal and dry-etching the SOI. The method can further comprise forming a template over the structure. The method can further comprise etching a portion of the SOI for removal under the metal. The method can further comprise growing a semiconductor where the portion of SOI was removed.

A nonlinear parametric device includes a planar substrate and a millimeter-wave resonator formed from superconductive material deposited on the planar substrate. When the resonator is cooled below a critical temperature, it exhibits nonlinear kinetic inductance that may be used to implement millimeter-wave nonlinear frequency generation and parametric amplification. Millimeter waves may be coupled into, and out of, the nonlinear parametric device with hollow rectangular electromagnetic waveguides. Niobium nitride is an excellent superconductive material for kinetic inductance due to its high intrinsic sheet inductance, a critical temperature that is higher than many other superconductive materials, and relatively low loss at millimeter-wave frequencies.