An active three-terminal superconducting device having an intersection region at which a hot spot may be controllably formed is described. The intersection region may exhibit current crowding in response to imbalances in current densities applied to channels connected to intersection region. The current crowding may form a hot spot, in which the superconducting device may exhibit a measurable resistance. In some cases, a three-terminal superconducting device may be configured to sense an amount of superconducting current flowing in a channel or loop without having to perturb the superconducting state or amount of current flowing in the channel. A three-terminal superconducting device may be used to read out a number of fluxons stored in a superconducting memory element.

A switchable Josephson junction is provided that includes a plurality of ferromagnetic insulators that are defined by their respective magnetic alignments. A first superconducting layer that is positioned between any two of the ferromagnetic insulators, wherein the conductive state is controlled by the relative magnetization orientation of the ferromagnetic insulators where the first superconducting layer is superconducting when the two magnetizations are aligned in antiparallel but it turns normally conducting when the magnetic alignment is parallel. A second superconducting layer is adjacent one of the ferromagnetic layers, wherein Josephson tunneling occurs between the first superconducting layer and second superconducting layer across one of the ferromagnetic layers.

An optical device includes a photonically controlled Josephson Junction and a Faraday rotator cell magnetized by the Josephson Junction.

A device includes a superconductor layer and a piezoelectric layer positioned adjacent to the superconductor layer. The piezoelectric layer is configured to apply a first strain to the superconductor layer in response to receiving a first voltage that is below a predefined voltage threshold and to apply a second strain to the superconductor layer in response to receiving a second voltage that is above the predefined voltage threshold. While the device is maintained below a superconducting threshold temperature for the superconductor layer and is supplied with current below a superconducting threshold current for the superconductor layer, the superconductor layer is configured to 1) operate in a superconducting state when the piezoelectric layer applies the first strain to the superconductor layer and 2) operate in an insulating state when the piezoelectric layer applies the second strain to the superconductor layer.

A semiconductor device includes a transmission circuit coupled between a first voltage supply node and a second voltage supply node, and suitable for outputting an output data signal corresponding to a data value to an output terminal during a data output enable period, and a switching circuit coupled between the first and second voltage supply nodes, and suitable for providing a current path between the first and second voltage supply nodes during a data output disable period.

An integrated, superconducting imaging sensor may be formed from a single, meandering nanowire. The sensor is capable of single-photon (or single-event) detection and imaging with 10 micron spatial resolution and sub-100-picosecond temporal resolution. The sensor may be readily scaled to large areas.

A device includes a first semiconductor layer; a portion of a second semiconductor layer disposed on the first semiconductor layer; and a third semiconductor layer including a first region disposed on the portion of the second semiconductor layer and a second region disposed on the first semiconductor layer. A thickness of the first region is less than a predefined thickness. The device also includes an etch stop layer disposed on the third semiconductor layer; a plurality of distinct portions of a fourth semiconductor layer disposed on the etch stop layer and exposing one or more distinct portions of the etch stop layer over the portion of the second semiconductor layer; and a plurality of distinct portions of a superconducting layer disposed on the plurality of distinct portions of the fourth semiconductor layer and the exposed one or more distinct portions of the etch stop layer.

A switchable Josephson junction is provided that includes a plurality of ferromagnetic insulators that are defined by their respective magnetic alignments. A first superconducting layer that is positioned between any two of the ferromagnetic insulators, wherein the conductive state is controlled by the relative magnetization orientation of the ferromagnetic insulators where the first superconducting layer is superconducting when the two magnetizations are aligned in antiparallel but it turns normally conducting when the magnetic alignment is parallel. A second superconducting layer is adjacent one of the ferromagnetic layers, wherein Josephson tunneling occurs between the first superconducting layer and second superconducting layer across one of the ferromagnetic layers.

Provided are a photon detection device and a photon detection method being practical, capable of performing photon detection in which no afterpulse is generated and generation of a dark count is suppressed, and capable of obtaining a high counting rate with low jitter. The photon detection device of the present invention includes: a photon detection section having a long plate-shaped superconducting stripline whose plate surface is a photon detection surface, and a bias current supply section supplying a bias current to the superconducting stripline; and a single flux quantum comparator circuit capable of detecting magnetic flux scattered from the superconducting stripline upon photon detection.

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.