A light-controlled superconductor uses electrons as carriers, which includes a light source and a sealed tube, wherein the sealed tube is made of glass or plastic. The sealed tube is filled with electron gas, and the light source produces incident light, and under the irradiation of the incident light, electrons will be forced to vibrate and behave similarly to vibrating electric dipoles, and emit secondary electromagnetic waves, so that the average distance between the electrons in the sealed tube is much smaller than the wavelength of the incident light, causing the vibrating electrons to be in a near-field of each other. When the electric field intensity direction of the incident light and the electric moments of two vibrating electrons are in the same radial straight line and are in the same direction, there exists an attractive force among the vibrating electrons.

A set of superconducting devices is interconnected in a lattice that is fabricated in a single two-dimensional plane of fabrication such that a superconducting connection can only reach a first superconducting device in the set while remaining in the plane by crossing a component of a second superconducting device that is also located in the plane. A superconducting coupling device having a span and a clearance height is formed in the superconducting connection of the first superconducting device. A section of the superconducting coupling device is separated from the component of the second superconducting device by the clearance in a parallel plane. A potential of a first ground plane on a first side of the component is equalized with a second ground plane on a second side of the component using the superconducting coupling device.

A method includes: providing a device having a first layer and a second layer in contact with a surface of the first layer, in which the second layer includes a first superconductor material; forming a buffer material on the second layer to form an etch buffer layer, in which an etch rate selectivity of the buffer material relative to the second layer upon exposure to a photoresist developer is such that the underlying second layer is not etched during exposure of the buffer layer to the photoresist developer; depositing and removing a selected portion of a resist layer to uncover a first portion of the etch buffer layer, wherein removing the selected portion of the resist layer comprises applying the photoresist developer to the selected portion of the resist layer.

A device for determining the parameters of strip-type superconductors includes a generator, a generator frequency-setting element, an inductance coil connected to the generator, a receiver, a receiver frequency-setting element, and an inductance coil connected to the receiver. The generator and receiver frequency-setting elements are same type narrow-band elements. The pass bands of the generator and receiver frequency-setting elements coincide through at least half of the bandwidth of the frequency-setting element having a narrower band pass width. The generator and receiver inductance coils are arranged with a gap between the same, making it possible for a strip-type superconductor to be placed between the inductance coils. The device is provided with a temperature sensor comprising a thermistor in contact with the superconductor. The device enables highly accurate and reproducible measurement results.

A system and method for treating a cavity comprises arranging a niobium structure in a coating chamber, the coating chamber being arranged inside a furnace, coating the niobium structure with tin thereby forming an Nb.sub.3Sn layer on the niobium structure, and doping the Nb.sub.3Sn layer with nitrogen, thereby forming a nitrogen doped Nb.sub.3Sn layer on the niobium structure.

Techniques for facilitating reduced thermal resistance attenuator on high-thermal conductivity substrates for quantum applications are provided. A device can comprise a substrate that provides a thermal conductivity level that is more than a defined thermal conductivity level. The device can also comprise one or more grooved transmission lines formed in the substrate. The one or more grooved transmission lines can comprise a powder substance. Further, the device can comprise one or more copper heat sinks formed in the substrate. The one or more copper heat sinks can provide a ground connection. Further, the one or more copper heat sinks can be formed adjacent to the one or more grooved transmission lines.

A technique relates to a superconducting microwave combiner. A first filter through a last filter connects to a first input through a last input, respectively. The first filter through the last filter each has a first passband through a last passband, respectively, such that the first passband through the last passband are each different. A common output is connected to the first input through the last input via the first filter through the last filter.

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.

Techniques for facilitating reduced thermal resistance attenuator on high-thermal conductivity substrates for quantum applications are provided. A device can comprise a substrate that provides a thermal conductivity level that is more than a defined thermal conductivity level. The device can also comprise one or more grooved transmission lines formed in the substrate. The one or more grooved transmission lines can comprise a powder substance. Further, the device can comprise one or more copper heat sinks formed in the substrate. The one or more copper heat sinks can provide a ground connection. Further, the one or more copper heat sinks can be formed adjacent to the one or more grooved transmission lines.

A technique relates to a superconducting microwave combiner. A first filter through a last filter connects to a first input through a last input, respectively. The first filter through the last filter each has a first passband through a last passband, respectively, such that the first passband through the last passband are each different. A common output is connected to the first input through the last input via the first filter through the last filter.