A superconducting device includes a first superconducting wire configured to carry a first current in a superconducting state, and to generate thermal energy upon occurrence of a hot spot during conduction. The device includes a second superconducting wire, thermally coupled to and electrically isolated from the first superconducting wire. The second superconducting wire is configured to conduct a second current in a superconducting state below, but sufficiently near its critical surface to be quenched to a non-superconducting state upon conduction of the thermal energy from the first superconducting wire.

The various embodiments described herein include methods, devices, and systems for fabricating and operating superconducting circuitry. In one aspect, an amplification circuit includes: (1) a superconducting component; (2) an amplifier coupled in parallel with the superconducting component such that the superconducting component is in a feedback loop of the amplifier; (3) a voltage source coupled to a first input of the amplifier; (4) one or more resistors coupled to a second input of the amplifier; and (5) an output terminal coupled to an output of the amplifier.

An electric circuit includes a plurality of superconducting components, each of the plurality of superconducting components having: a respective first terminal; a respective second terminal; and a respective input. The electric circuit further includes a bias current source electrically-connected to the respective first terminal of each of the plurality of superconducting components. The bias current source is configured to provide a bias current adapted to cause the electric circuit to function as a logical OR gate on the respective inputs of the plurality of superconducting components. The electric circuit further includes an output node adapted to output a state of the logical OR gate.

Described is a method comprising directing an ultra-low voltage electron beam to a surface of a first insulating layer. The first insulating layer is disposed on a second insulating layer. The method includes modifying, by the application of the ultra-low voltage electron beam, the surface of the first insulating layer to selectively switch an interface between a first state having a first electronic property and a second state having a second electronic property.

Described is a method comprising directing an ultra-low voltage electron beam to a surface of a first insulating layer. The first insulating layer is disposed on a second insulating layer. The method includes modifying, by the application of the ultra-low voltage electron beam, the surface of the first insulating layer to selectively switch an interface between a first state having a first electronic property and a second state having a second electronic property.

A system for connecting superconducting tapes in a superconducting fault current limiter (SCFCL) system is disclosed. The novel connector system allows two superconducting tapes to be installed in a single opening in a connector stack. This reduced the height of the connector stack by nearly 50%, making the SCFCL system more efficient and smaller in volume. In one embodiment, each connector has a recessed portion on both the top and bottom surfaces, such that when stacked on another connector, the recessed portions align, forming a larger opening. In another embodiment, the connector has a single recessed portion that can accommodate two superconducting tapes. The superconducting tapes may be disposed in a protective sleeve.

The various embodiments described herein include methods, devices, and systems for fabricating and operating superconducting circuitry. In one aspect, an amplification circuit includes: (1) a superconducting component; (2) an amplifier coupled in parallel with the superconducting component such that the superconducting component is in a feedback loop of the amplifier; (3) a voltage source coupled to a first input of the amplifier; (4) one or more resistors coupled to a second input of the amplifier; and (5) an output terminal coupled to an output of the amplifier.

An electronic device (e.g., a superconducting memory cell) includes a substrate and a layer of superconducting material disposed over the substrate. The layer of superconducting material is patterned to form a plurality of distinct instances of the layer of superconducting material including: a first wire; and a loop that is (i) distinct and separate from the first wire and (ii) capacitively coupled to the first wire while the loop and the first wire are in a superconducting state. The loop is configured to form a persistent current via the capacitive coupling in response to a write current applied to the first wire while the loop and the first wire are in the superconducting state. The persistent current represents a logic state of the electronic device.

A current limiter arrangement limiting an electric current between a first and a second terminal includes a first current limiting device and a second current limiting device arranged between the first and the second terminal. The first and the second current limiting device each include a substrate having a substrate surface area and a substrate thickness, and include a superconducting section arranged on the substrate and thermally coupled to the substrate thereby covering a coupling surface area on the substrate. Each of the superconducting sections has a critical current value and the substrate surface areas, the substrate thicknesses and or the coupling surface areas are implemented as a function of the critical current values.

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.