Abstract: A reciprocal quantum logic (RQL) latch system is provided. The latch system comprises an output portion that retains a state of the latch system, and a bi-stable loop that comprises a set input, a reset input and an output coupled to the output portion. A positive single flux quantum (SFQ) pulse on the set input when the latch system is in a reset state results in providing a SFQ current in the output portion representative of the latch system being in a set state.

Abstract: An electronic filtering device includes continuous trace on a dielectric substrate and a dissipation layer communicatively coupled to the trace. The dissipation layer may include disconnected metal particles, which may be embedded in a substrate, for example in an epoxy. The continuous trace may be meandering, for example crenulated, coil or spiral signal path. At least a second continuous trace may be spaced from the first by the substrate, and conductively coupled by a via. The electronic filtering device may be used in one or more printed circuit boards (PCBs) that form stages of an input/output system.

Abstract: Use, as a component with variable inductance which is a function of the current passing through it, of an inductive superconductive component having at least two terminals and comprising at least one line segment working with said terminals and integrating at least one of these terminals, this line segment constituting a conductive or superconductive layer within a stack of films alternately superconductive and insulating.

Abstract: Systems and methods are disclosed relating to transmission of communications via high frequency antenna systems employing high-temperature superconductor filters and/or amplifiers. In certain embodiments, a comb linear amplifier combiner may be modified with, for example, cryogenically cooled and/or high-temperature superconductor components, such as matching units of bandpass filters. A computer control unit may be coupled to the transmission circuit to control operation of one or more of the low-power transmitters, filters, and/or amplifiers.

Abstract: Based on its superconductive properties relating to “nonlineanty,” a conventional HTS strip is divisible into three “domains,” namely, a medial domain and two lateral domains. The nonlinearity associated with the conventional strip's medial domain is considerably greater than that which is associated with its lateral domains. Similarly divisible into a medial domain and two lateral domains, the present invention's HTS strip uniquely exploits these physical distinctions by causing more (e.g., most) of the current that it conducts to be conducted by its lateral domains. Various inventive designs accomplish this through narrowing or interruption/punctuation (e.g., via holes and/or trenches) or degradation, or some combination thereof, of the medial domain. By thus “re-proportioning” current conduction as compared with a conventional strip, an inventive strip succeeds in “re-proportioning” the associated nonlinearities.

Abstract: A rapid SFQ one-way buffer (13, 1, 4, 5, 15, 2 & 9), is combined with a Josephson transmission line (17,3, 19, 16, 21 & 4) that is lightly loaded (RL) to provide a superconductor driver capable of producing double flux quantum output pulses. Each SFQ pulse applied to the input of the one-way buffer propagates through the Josephson transmission line to generate a double flux quantum pulse at the transmission line output.

Abstract: A quantum cryptography multi-node communication system includes a quantum communication channel and a plurality of nodes including a transmission node and a reception node and connected with the quantum communication channel. The transmission node transmits a light signal as a time series of photons to the reception node through the quantum communication channel, a quantum state of the photons is modulated, and transmits a quantum state sequence to the reception node. The reception node predetermines a quantum state sequence, receives the light signal transmitted from the transmission node, measures quantum states of the received light signal, and determines presence or absence of interception based on the predetermined quantum state sequence, the transmitted quantum state sequence and the measured quantum states.

Abstract: A superconductor signal amplifier which receives an extremely small high-frequency signal having a frequency of tens of GHz generated in a superconductive circuit, amplifies the voltage of the high-frequency signal without a decrease in frequency, and outputs the thus amplified high-frequency signal from the superconductive circuit. At an output part of a single flux quantum circuit using a flux quantum as a binary information carrier, there are provided a superconductive junction line for flux quantum transmission and a splitter for simultaneously producing two flux quanta from a flux quantum. According to the number of plural series-connected SQUIDs, a plurality of flux quantum signals are generated and input to the plural series-connected SQUIDs so that the SQUIDs are simultaneously switched to a voltage state. In each SQUID pair comprising two SQUIDs, a part of an inductor is shared by the two SQUIDs for reduction in inductance, thereby increasing an output voltage of the series-connected SQUIDs.

Abstract: A semiconductor device including a damascene superconducting interconnect, formed of a Ba—Cu—Ca—O superconducting material. A method of forming a superconducting damascene interconnect structure, and the structure made thereby, the method including forming a cavity in an interlevel dielectric; forming a barrier layer in the cavity; forming a seed layer in the cavity over the barrier layer; forming a Cu—Ba alloy layer; filling the cavity by depositing a Cu—Ca—O film; and annealing in oxygen flow to form a Ba—Cu—Ca—O superconductor on the barrier layer. In an alternate embodiment, no barrier layer is formed.

Abstract: A transmission line antenna assembly having a substantially continuous bandwidth from the microwave region of the electromagnetic spectrum to the VHF region of the spectrum. The antenna assembly includes at least one balanced transmission line antenna element of high-temperature superconductor material supported by a substrate, an antenna cavity supporting the substrate and containing a thermally-conductive electromagnetic-energy-absorbing material therein, and a cryogenic cooler for cooling the antenna element to a temperature at which it exhibits superconductivity.

Abstract: A lanthanum aluminate (LaAlO3) substrate on which thin films of layered perovskite copper oxide superconductors are formed. Lanthanum aluminate, with a pseudo-cubic perovskite crystal structure, has a crystal structure and lattice constant that closely match the crystal structures and lattice constants of the layered perovskite superconductors. Therefore, it promotes epitaxial film growth of the superconductors, with the crystals being oriented in the proper direction for good superconductive electrical properties, such as a high critical current density. In addition, LaAlO3 has good high frequency properties, such as a low loss tangent and low dielectric constant at superconductive temperatures. Finally, lanthanum aluminate does not significantly interact with the superconductors. Lanthanum aluminate can also used to form thin insulating films between the superconductor layers, which allows for the fabrication of a wide variety of superconductor circuit elements.

Abstract: A method and apparatus for temperature activated protection of electronic components from interfering electromagnetic radiation comprising the step of shielding of a component with a thin film of superconducting material characterized by a critical temperature of at least 93.degree.K, and exposing the film to a temperature below the critical temperature. To allow transmissions to and from the component, the shield is converted to a window by heating the film to a temperature above the critical temperature.

Abstract: In a superconductor mixer, a non-linear element is provided on a substrate. The non-linear element comprises at least one Josephson junction connected in series. An antenna pattern of superconductor, an intermediate frequency output pattern of superconductor, and a bias current pattern of superconductor are connected to the non-linear element. A signal high frequency wave (RF) and a local reference frequency wave (LO) are received by the antenna pattern and then absorbed in the non-linear element to obtain an intermediate frequency (IF) signal. Then, with applying a current to the series connected Josephson junction in the non-linear element from the bias current pattern, the intermediate frequency (IF) signal as a frequency signal of a difference between the signal high frequency wave (RF) and the local reference frequency wave (LO) is output to the intermediate frequency output pattern.

Abstract: A signal receiving system has an antenna assembly divided into sectors. Each sector employs diversity by having at least two antennae for receiving signals from that sector. Signals from the antennae are passed to filters where the filters contain superconductors requiring cooling. The filters are housed in cryocoolers in a manner such that no cryocooler contains more than one filter receiving signals from a given sector. After filtering, the signals are sent to diversity receivers which combine or compare signals from antennae in the same sector.

Abstract: The invention provides a wide frequency band high temperature superconductor mixer antenna which allows a superconductor feed line, which exhibits a high resistance loss in a high frequency region, to be used in a low frequency region with a low loss and which is provided with a same structure as a mixer which has a wide band twice or more the frequency of a millimeter or more wave while keeping a characteristic of a high integration array antenna, which makes most of the high integrity of superconductor feed lines. The wide frequency band high temperature superconductor mixer antenna includes one or a plurality of planar structure antenna patterns of the log-periodical type or the log-spiral type and a plurality of oxide superconductor thin film feed line wiring patterns formed on a same face of a main surface of a substrate, a central portion of each of the planar structure antenna patterns being formed from an oxide superconductor thin film on which a non-linear element part is provided.

Abstract: Microwave harmonic mixer circuit of SQUID(Superconducting Quantum Interference Device) is disclosed, in which a magnetic flux to voltage conversion characteristics of SQUID is used for generating a higher harmonics from an LO(Local Oscillator) signal, and mixing the higher LO harmonics with a radio frequency(RF) signal, including an SQUID for adding a RF(Radio Frequency) signal to a magnetic flux of an LO(Local Oscillator) signal frequency for having a mixing of the frequencies done; a current applying part and a grounding part disposed on both sides of the SQUID and connected to a current source on one side and grounded on the other side respectively for supplying operation current to the SQUID; RF antenna parts one each disposed between the SQUID and the current applying part and the SQUID and the grounding part for feeding a RF signal into the SQUID; an LO signal source and antenna part for applying a flux of an LO signal frequency to the SQUID; and, an IF signal detecting part for detecting an IF(Intermed

Abstract: A high frequency receiver detects and downconverts 50-1,000 GHz radio frequency signals using a receiver consisting of a lens and planar antenna, pre-amplifier, mixer, local oscillator, and IF-amplifier. The insulating dielectric lens is used to focus terahertz radio frequency signals onto the thin film antenna. The preamplifier amplifies these faint signals so that they can be downconverted into an intermediate frequency by the mixer and local oscillator. The mixer is a dual port device which provides isolation of the local oscillator and input signal to avoid saturation of the preamplifier. The IF amplifier boosts the amplitude of the downconverted IF signal produced by the mixer.