Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum processing device may include a quantum well stack, the quantum well stack includes a quantum well layer, the quantum processing device further includes a plurality of gates above the quantum well stack to control quantum dot formation in the quantum well stack, and (1) gate metal of individual gates of the array of gates is tapered so as to narrow farther from the quantum well stack or (2) top surfaces of gate metal of individual gates of the array of gates are dished.

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 base; a fin extending away from the base, wherein the fin includes a quantum well layer; a first dielectric material around a bottom portion of the fin; and a second dielectric material around a top portion of the fin, wherein the second dielectric material is different from the first dielectric material.

A low-noise wide band amplifier is realized utilizing a superconductor-insulator-superconductor (SIS) junction, quasiparticle frequency mixers connected in tandem or in cascade, a first quasiparticle mixer performs first frequency mixing with use of a first local signal having a frequency not less than twice a frequency of an input signal to the first quasiparticle mixer, a second quasiparticle mixer performs second frequency mixing with use of a second local signal having a frequency not more than twice a frequency of an input signal to the second quasiparticle mixer, and signal amplification is performed through frequency conversion by extracting, from among a plurality of signals generated with the first and the second frequency mixing, a signal in a frequency band not more than a frequency band of the signal before the first frequency mixing and the second frequency mixing, using a transmission line or a filter.

Quantum dot devices, and related systems and methods, are disclosed herein. In some embodiments, a quantum dot device may include a quantum well stack having a first face and a second opposing face; an array of parallel first gate lines at the first face or the second face of the quantum well stack; and an array of parallel second gate lines at the first face or the second face of the quantum well stack, wherein the second gate lines are oriented diagonal to the first gate lines.

Quantum dot devices, and related systems and methods, are disclosed herein. In some embodiments, a quantum dot device may include a quantum well stack; a plurality of first gate lines above the quantum well stack; a plurality of second gate lines above the quantum well stack, wherein the second gate lines are perpendicular to the first gate lines; and an array of regularly spaced magnet lines.

Devices and methods that can facilitate hybrid under-bump metallization components are provided. According to an embodiment, a device can comprise an under-bump metallization component that can comprise a superconducting interconnect component and a solder wetting component. The device can further comprise a solder bump that can be coupled to the superconducting interconnect component and the solder wetting component. In some embodiments, the superconducting interconnect component can comprise a hermetically sealed superconducting interconnect component.

The various embodiments described herein include methods, devices, and systems for fabricating and operating transistors. In one aspect, a transistor includes: (1) a semiconducting component configured to operate in an on state at temperatures above a semiconducting threshold temperature; and (2) a superconducting component configured to operate in a superconducting state while: (a) a temperature of the superconducting component is below a superconducting threshold temperature; and (b) a first current supplied to the superconducting component is below a current threshold; where: (i) the semiconducting component is located adjacent to the superconducting component; and (ii) in response to a first input voltage, the semiconducting component is configured to generate an electromagnetic field sufficient to lower the current threshold such that the first current exceeds the lowered current threshold, thereby transitioning the superconducting component to a non-superconducting state.

The various implementations described herein include methods, devices, and systems for detecting light. In one aspect, a photodetector device includes: a superconducting wire, and a transistor that includes a semiconducting component and a superconducting component. The superconducting wire is electrically coupled to the superconducting component. The semiconducting component is located adjacent to the superconducting component. The superconducting component is configured to, in response to receiving an input current exceeding a current threshold, transition from a superconducting state to a non-superconducting state and generate heat sufficient to increase a temperature of the semiconducting component from a temperature below a semiconducting threshold temperature to a temperature above the semiconducting threshold temperature.

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 quantum well stack; a first gate above the quantum well stack, wherein the first gate includes a first gate metal and a first gate dielectric; and a second gate above the quantum well stack, wherein the second gate includes a second gate metal and a second gate dielectric, and the first gate is at least partially between a portion of the second gate and the quantum well stack.

The present disclosure relates to nanoscale device comprising an elongated crystalline nanostructure, such as a nanowire crystal, a nanowhisker crystal or a nanorod crystal, and a method for producing thereof. One embodiment relates to a nanoscale device comprising an elongated crystalline semiconductor nanostructure, such as a nanowire (crystal) or nanowhisker (crystal) or nanorod (crystal), having a plurality of substantially plane side facets, a crystalline structured first facet layer of a superconductor material covering at least a part of one or more of said side facets, and a second facet layer of a superconductor material covering at least a part of the first facet layer, the superconductor material of the second facet layer being different from the superconductor material of the first facet layer, wherein the crystalline structure of the semiconductor nanostructure is epitaxially matched with the crystalline structure of the first facet layer on the interface between the two crystalline structures.