Abstract: An electronic component (10, 110) is designed as a semiconductor or with a semiconductor-like structure for moving a quantum dot (68, 168) over a distance. The electronic component (10, 110) comprises a substrate (32, 132) having a two-dimensional electron gas or electron hole gas. A gate electrode assembly (16, 18, 20, 116, 118, 120) having gate electrodes (38, 40, 42, 44, 138, 140, 142, 144) is arranged on a surface (31, 131) of the electronic component (10, 110). The gate electrode assembly (16, 18, 20, 116, 118, 120) produces a potential well (66, 166) in the substrate (32, 132). Electrical terminals for connecting the gate electrode assembly (16, 18, 20, 116, 118, 120) to voltage sources are provided for this purpose. The disclosure further relates to a method for such an electronic component (10, 110).

Abstract: Methods, systems and apparatus for implementing iSWAP quantum logic gates between a first qubit and a second qubit. In one aspect, a method includes implementing a cascade schedule that defines a trajectory of a detuning between a frequency of the first qubit and a frequency of the second qubit. Implementing the cascade schedule includes: during a first stage, adiabatically driving detuning between the frequency of the first qubit and the frequency of the second qubit through a first avoided crossing in a leakage channel; during a second stage, driving detuning between the frequency of the first qubit and the frequency of the second qubit through a second avoided crossing in a swap channel; during a third stage, evolving the first qubit and second qubit; during a fourth stage, implementing the second stage in reverse order; and during a fifth stage, implementing the first stage in reverse order.

Abstract: A method of setting up a quantum circuit for computational basis state shift. For the quantum circuit, a first quantum register, a second quantum register and a first ancilla register are set up. The first quantum register includes four qubits and the second quantum register includes N?4 qubits. To the first quantum register, the second quantum register and the first ancilla register are applied in a sequential order: (i) an initial step including three CX gates and a first X gate; (ii) a first segment including seven multi-controlled gates; (iii) a second segment comprising a first set of CX gates, a second set of CX gates and a cascade of gates arranged between the first set and the second set; and (iv) a third segment comprising two CX gates and a second X gate.

Abstract: Methods, systems, and apparatus for individual qubit excitation control with a global excitation drive. In one aspect, a method includes accessing a quantum system that comprises a plurality of qubits; a plurality of qubit frequency control lines, each qubit frequency control line corresponding to an individual qubit and controlling the frequency of the qubit; a driveline; a plurality of couplers, each coupler coupling a corresponding qubit to the driveline so that a plurality of qubits are coupled to the driveline; determining one or more qubits that require a rotation operation; for each qubit requiring a rotation operation: tuning the qubit frequency to the corresponding driveline frequency of the rotation operation; performing the rotation operation using a microwave pulse on the excitation drive; and tuning the qubit away from the driveline frequency of the rotation operation.

Abstract: According to one embodiment, an electronic circuit includes a superconducting element and a supplier. The superconducting element includes first and second conductive components. The first conductive component includes first and second ends, and a first portion. The first end is capacitively coupled to a first quantum bit having a first characteristic frequency. The second end is capacitively coupled to a second quantum bit having a second characteristic frequency. The first portion is between the first and second ends. The second conductive component includes third end and fourth ends, and a Josephson junction provided between the third and fourth ends. The fourth end is capacitively coupled to the first portion. The supplier supplies a microwave to the third end. The microwave includes one of a first, a second, or a third wave. The second wave includes fourth and fifth waves. The third wave includes sixth and seventh waves.

Abstract: Topologies for analog computing systems are provided. Qubits in the topology are grouped into cells, and cells are coupled to adjacent cells by inter-cell couplers. At least some cells are coupled to non-adjacent cells via long-range couplers. Long-range couplers may be arranged into coverings so that certain sets of qubits within a covering region may be coupled with a reduced number of couplers. Each cell within a covering region without a long-range coupler may be proximate to a cell with a long range coupler so that each cell within the covering region is no more than a certain coupling distance away from a long-range coupler. Long-range couplers may couple over a greater physical distance than inter-cell couplers. Long-range couplers may couple to qubits over a larger coupling region, and may extend across multiple crossing regions between qubits.

Abstract: One example includes a superconducting gate system. The system includes a first input that is configured to provide a first input pulse and a second input that is configured to provide a second input pulse. The system also includes a gate configured to provide a first output pulse at a first output corresponding to a first logic function with respect to the first and second input pulses and based on a positive bias inductor and a first Josephson junction that are each coupled to the first output. The gate is also configured to provide a second output pulse at a second output corresponding to a second logic function with respect to the first and second input pulses and based on a negative bias inductor and a second Josephson junction that are each coupled to the second output.

Abstract: A tunable superconducting circuit includes a first charge island, a second charge island, a third charge island, a fourth charge island, a first junction loop electrically coupled to the first and third charge islands, a second junction loop coupled to the second and third charge islands and a third junction loop coupled to the third and fourth charge islands, wherein the first, second and third junction loops are tuned in frequency to operate together as a qubit.

Abstract: A binary half-adder comprising first and second oscillators, each oscillator being connected to a first input and to a second input, the second oscillator being connected to the first oscillator, wherein the first oscillator is configured to oscillate if the first input is high or the second input is high, the second oscillator is configured to oscillate if the first and the second inputs are high, and wherein the connection between the second oscillator and the first oscillator is configured to suppress oscillation of the first oscillator if the second oscillator is oscillating.

Abstract: Preservation of quantum entanglement in a two-qubit system is achieved by use of the disclosed systems. Three different example two-qubit systems are shown: (1) a system employing a weak measurement, (2) a system in which a generalized amplitude dampening occurs without use of a weak measurement, and (3) an extended system in which the system is prepared in a more robust state less susceptible to decoherence prior to a generalized amplitude dampening.

Abstract: Analog processors for solving various computational problems are provided. Such analog processors comprise a plurality of quantum devices, arranged in a lattice, together with a plurality of coupling devices. The analog processors further comprise bias control systems each configured to apply a local effective bias on a corresponding quantum device. A set of coupling devices in the plurality of coupling devices is configured to couple nearest-neighbor quantum devices in the lattice. Another set of coupling devices is configured to couple next-nearest neighbor quantum devices. The analog processors further comprise a plurality of coupling control systems each configured to tune the coupling value of a corresponding coupling device in the plurality of coupling devices to a coupling. Such quantum processors further comprise a set of readout devices each configured to measure the information from a corresponding quantum device in the plurality of quantum devices.

Abstract: A computing structure is described. The computing structure includes at least one logic gate. The at least one logic gate has an arrangement of nano-particles configured to propagate localized plasmon-polaritons (LLPs). The logic gate may have a gate state and be configured to perform a logic function based on a desired logical output.

Abstract: Superconducting single flux quantum circuits are disclosed herein, each having at least one Josephson junction which will flip when the current through it exceeds a critical current. Bias current for the Josephson junction is provided by a biasing transformer instead of a resistor. The lack of any bias resistors ensures that unwanted power dissipation is eliminated.

Abstract: A system for performing digital operations, including a first device configured to transform a digital input into one or more signals, at least one AB ring, the at least one AB ring irreducibly-coupled and configured to include at least three terminals, a second device configured to read a portion of a signal expressed upon two or more of the at least three terminals, and a third device configured to transform the portion of the signal expressed upon two or more of the at least three terminals into a digital output, the third device operationally connected to the second device.

Abstract: The present disclosure relates to methods and systems for data tag control for quantum dot cellular automata (QCA). An example method includes receiving data, associating a data tag with the data, communicating the data tag along a first wire-like element to a local tag decoder, reading instructions from the data tag using the local tag decoder, communicating the instructions to a processing element, communicating the data along a second wire-like element to the processing element, and processing the data with the processing element according to the instructions. A length of the first wire-like elements and a length of the second wire-like element are approximately the same such that communication of the instructions and the data to the processing element are synchronized.

Abstract: The present disclosure relates to methods and systems for data tag control for quantum dot cellular automata (QCA). An example method includes receiving data, associating a data tag with the data, communicating the data tag along a first wire-like element to a local tag decoder, reading instructions from the data tag using the local tag decoder, communicating the instructions to a processing element, communicating the data along a second wire-like element to the processing element, and processing the data with the processing element according to the instructions. A length of the first wire-like elements and a length of the second wire-like element are approximately the same such that communication of the instructions and the data to the processing element are synchronized.

Abstract: Micromagnetic elements, logic devices and methods of fabricating and using them to store data and perform logic operations are disclosed. Micromagnetic elements for data storage, as well as those providing output from a logic device, are at least partially covered with an optical coating that facilitates determination of the magnetic state. The disclosed logic devices perform one or more of AND, OR, NAND and NOR operations.

Abstract: In one embodiment, the disclosure relates to a method and apparatus for controlling the energy state of a qubit by bringing the qubit into and out of resonance by coupling the qubit to a flux quantum logic gate. The qubit can be in resonance with a pump signal, with another qubit or with some quantum logic gate. In another embodiment, the disclosure relates to a method for controlling a qubit with RSFQ logic or through the interface between RSFQ and the qubit.

Abstract: A transverse coupling system may include a first qubit, a second qubit, a first conductive path capacitively connecting the first qubit and the second qubit, a second conductive path connecting the first qubit and the second qubit, and a dc SQUID connecting the first and the second conductive paths wherein the compound junction loop is threaded by an amount of magnetic flux.

Abstract: Systems and methods are provided for performing a quantum gate operation. A first classical control parameter, configured to tune an associated frequency of a first qubit, is adjusted from a first value to a second value. The first value is selected such that the first qubit is tuned far from a characteristic frequency of an associated resonator, and the second value is selected such that the first qubit is tuned near to the characteristic frequency of the resonator. A second classical control parameter, configured to tune an associated frequency of a second qubit, is adjusted from a third value to a fourth value. The third value is selected such that the second qubit is tuned far from the characteristic frequency of the resonator. The first classical control parameter is returned to the first value. The second classical control parameter is returned to the third value.

Abstract: Superconducting single flux quantum circuits are disclosed herein, each having at least one Josephson junction which will flip when the current through it exceeds a critical current. Bias current for the Josephson junction is provided by a biasing transformer instead of a resistor. The lack of any bias resistors ensures that unwanted power dissipation is eliminated.

Abstract: Nanotube based logic driver circuits. These include pull-up driver circuits, push-pull driver circuits, tristate driver circuits, among others. Under one embodiment, an off-chip driver circuit includes a differential input having first and second signal links, each coupled to a respective one of two differential, on-chip signals. At least one output link is connectable to an off-chip impedance load, and at least one switching element has an input node, an output node, a nanotube channel element, and a control structure disposed in relation to the nanotube channel element to controllably form and unform an electrically conductive channel between said input node and said output node. The input node is coupled to a reference signal and the control structure is coupled to the first and second signal links. The output node is coupled to the output link, and the channel element is sized to carry sufficient current to drive said off-chip impedance load.

Abstract: A system for communicably coupling between two superconducting qubits may include an rf-SQUID coupler having a loop of superconducting material interrupted by a compound Josephson junction and a first magnetic flux inductor configured to controllably couple to the compound Josephson junction. The loop of superconducting material may be positioned with respect to a first qubit and a second qubit to provide respective mutual inductance coupling therebetween. The coupling system may be configured to provide ferromagnetic coupling, anti-ferromagnetic coupling, and/or zero coupling between the first and second qubits. The rf-SQUID coupler may be configured such that there is about zero persistent current circulating in the loop of superconducting material during operation.

Abstract: Systems and methods are provided for performing a quantum gate operation. A first classical control parameter is associated with a first qubit and coupled to a resonator. The first classical control parameter is transitioned from a first control value to a second control value. The first classical control parameter is returned from the second control value to the first control value via an adiabatic sweep operation, as to permit a transfer of energy between the first qubit and the resonator that causes a change in the quantum state of the qubit and resonator.

Abstract: In one embodiment, the disclosure relates to a single flux quantum (SFQ) signal transmission line powered by an AC power source. The AC power source supplies power to a transformer having a primary winding and a secondary winding. The primary winding receives the AC signal and the secondary winding communicates the signal to the SFQ transmission line. The transmission line can optionally include an input filter circuit for receiving the incoming SFQ pulse. The filter circuit can have a resistor and an inductor connected in parallel. In an alternative arrangement, the filter circuit can comprise of an inductor. A first Josephson junction can be connected to the filter circuit and to the secondary winding. The Josephson junction triggers in response to the incoming SFQ pulse and regenerates a pulse signal in response to a power discharge from the secondary winding.

Abstract: In one embodiment, the disclosure relates to a single flux quantum (SFQ) signal transmission line powered by an AC power source. The AC power source supplies power to a transformer having a primary winding and a secondary winding. The primary winding receives the AC signal and the secondary winding communicates the signal to the SFQ transmission line. The transmission line can optionally include an input filter circuit for receiving the incoming SFQ pulse. The filter circuit can have a resistor and an inductor connected in parallel. In an alternative arrangement, the filter circuit can comprise of an inductor. A first Josephson junction can be connected to the filter circuit and to the secondary winding. The Josephson junction triggers in response to the incoming SFQ pulse and regenerates a pulse signal in response to a power discharge from the secondary winding.

Abstract: Supercooled electronics often use Rapid Single Flux Quantum (RSFQ) digital circuits. The output voltages from RSFQ devices are too low to be directly interfaced with semiconductor electronics, even if the semiconductor electronics are cooled. Techniques for directly interfacing RSFQ digital circuits with semiconductor electronics are disclosed using a novel inverting transimpedance digital amplifier in conjunction with a non-inverting transimpedance digital amplifier to create a differential transimpedance digital amplifier that permits direct interfacing between RSFQ and semiconductor electronics.

Abstract: In one embodiment, the disclosure relates to a single flux quantum (SFQ) signal transmission line powered by an AC power source. The AC power source supplies power to a transformer having a primary winding and a secondary winding. The primary winding receives the AC signal and the secondary winding communicates the signal to the SFQ transmission line. The transmission line can optionally include an input filter circuit for receiving the incoming SFQ pulse. The filter circuit can have a resistor and an inductor connected in parallel. In an alternative arrangement, the filter circuit can comprise of an inductor. A first Josephson junction can be connected to the filter circuit and to the secondary winding. The Josephson junction triggers in response to the incoming SFQ pulse and regenerates a pulse signal in response to a power discharge from the secondary winding.

Abstract: Nanotube-based logic circuitry is disclosed. Tri-stating elements add an enable/disable function to the circuitry. The tri-stating elements may be provided by nanotube-based switching devices. In the disabled state, the outputs present a high impedance, i.e., are tri-stated, which state allows interconnection to a common bus or other shared communication lines. In embodiments wherein the components are non-volatile, the inverter state and the control state are maintained in the absence of power. Such an inverter may be used in conjunction with and in the absence of diodes, resistors and transistors or as part of or as a replacement to CMOS, biCMOS, bipolar and other transistor level technologies.

Abstract: Systems and methods are provided for performing a quantum gate operation. A first classical control parameter is associated with a first qubit and coupled to a resonator. The first classical control parameter is transitioned from a first control value to a second control value. The first classical control parameter is returned from the second control value to the first control value via an adiabatic sweep operation, as to permit a transfer of energy between the first qubit and the resonator that causes a change in the quantum state of the qubit and resonator.

Abstract: Superconducting single flux quantum circuits are disclosed herein, each having at least one Josephson junction which will flip when the current through it exceeds a critical current. Bias current for the Josephson junction is provided by a biasing transformer instead of a resistor. The lack of any bias resistors ensures that unwanted power dissipation is eliminated.

Abstract: A quantum logic gate is formed from multiple qubits coupled to a common resonator, wherein quantum states in the qubits are transferred to the resonator by transitioning a classical control parameter between control points at a selected one of slow and fast transition speeds, relative to the characteristic energy of the coupling, whereby a slow transition speed exchanges energy states of a qubit and the resonator, and a fast transition speed preserves the energy states of a qubit and the resonator.

Abstract: Systems and methods for copying the classical state of a source qubit to a target qubit are provided. These techniques may be used to read out the states of an array of qubits.

Abstract: A Quantum-dot Cellular Automata (QCA) device having normal QCA cells laid out in a planar structure such that there are a set of input lines, that may be columns, and a set of orthogonal, output lines, that may be rows. The device has clocking regions that control the flow of binary signals through the device. The input columns are driven by a separate input signal, and all the cells of each column align to match their input signal. These input columns then serve as drivers for output rows that act as serial shift registers under the control of clock signals applied to sub-sections of the rows. In this way, a copy of the contents of each of the input signals propagates along each of the output rows to an output cell. The output cells of each output row may be assigned their own, latching clock signal.

Abstract: Supercooled electronics often use Rapid Single Flux Quantum (RSFQ) digital circuits. The output voltages from RSFQ devices are too low to be directly interfaced with semiconductor electronics, even if the semiconductor electronics are cooled. Techniques for directly interfacing RSFQ digital circuits with semiconductor electronics are disclosed using a novel inverting transimpedance digital amplifier in conjunction with a non-inverting transimpedance digital amplifier to create a differential transimpedance digital amplifier that permits direct interfacing between RSFQ and semiconductor electronics.

Abstract: A quantum logic gate is formed from multiple qubits coupled to a common resonator, wherein quantum states in the qubits are transferred to the resonator by transitioning a classical control parameter between control points at a selected one of slow and fast transition speeds, relative to the characteristic energy of the coupling, whereby a slow transition speed exchanges energy states of a qubit and the resonator, and a fast transition speed preserves the energy states of a qubit and the resonator.

Abstract: A quantum device comprises first conductive members and second conductive members confining carriers in the z direction and having two dimensional electron gas on the xy plane. Third conductive members generating an electric field having an effect on the first conductive members. An insulating member easily passing a tunnel current between the first conductive members and the second conductive members. Another insulating member hardly passing a tunnel current between the first conductive members and the third conductive members. An electric field generated by a potential applied to the third conductive members has an effect on the sub-band of the first conductive members.

Abstract: A quantum computer can only function stably if it can execute gates with extreme accuracy. “Topological protection” is a road to such accuracies. Quasi-particle interferometry is a tool for constructing topologically protected gates. Assuming the corrections of the Moore-Read Model for ?=5/2's FQHE (Nucl. Phys. B 360, 362 (1991)) we show how to manipulate the collective state of two e/4-charge anti-dots in order to switch said collective state from one carrying trivial SU(2) charge, |1>, to one carrying a fermionic SU(2) charge |?>. This is a NOT gate on the {|1>, |?>} qubit and is effected by braiding of an electrically charged quasi particle ? which carries an additional SU(2)-charge. Read-out is accomplished by ?-particle interferometry.

Abstract: The present invention relates to CML(Current Mode Logic)-type input driving method and tunneling diode logic using MOBILE(Monostable Nistable transition Logic Element) configuration, as kinds of very high-speed digital logic circuits. The objectives of the present invention are to improve the disadvantage of MOBILE circuit configuration that is an existing tunneling diode logic, and at the same time provide new MOBILE based logic functions. Wherein, the difficulty for input voltage adjustment is resolved by replacing the input part with a CML input driving gate, and speed problem due to transistor is resolved. Moreover, a plurality of logic functions such as inverted return-to-zero D flip-flop, non-inverted return-to-zero D flip-flop, return-to-zero OR gate, return-to-zero D flip-flop generating differential output, and optical flip-flop are implemented.

Abstract: A quantum computer can only function stably if it can execute gates with extreme accuracy. “Topological protection” is a road to such accuracies. Quasi-particle interferometry is a tool for constructing topologically protected gates. Assuming the corrections of the Moore-Read Model for ?= 5/2's FQHE (Nucl. Phys. B 360, 362 (1991)) we show how to manipulate the collective state of two e/4-charge anti-dots in order to switch said collective state from one carrying trivial SU(2) charge, |1>, to one carrying a fermionic SU(2) charge |?>. This is a NOT gate on the {|1>, |?>} qubit and is effected by braiding of an electrically charged quasi particle ? which carries an additional SU(2)-charge. Read-out is accomplished by ?-particle interferometry.

Abstract: Routing and distribution of radio-frequency (RF) signals is commonly achieved in the analog domain. However, improved performance and simplified circuit architectures may be obtained by first digitizing the RF signal, and then carrying out all routing in the digital domain. A new generation of scalable digital switches has been developed, which routes both the data and clock signals together, this being necessary to maintain the integrity of the digitized RF signal. Given the extremely high switching speeds necessary for these applications (tens of GHz), this is implemented using Rapid-Single-Flux-Quantum (RSFQ) logic with superconducting integrated circuits. Such a digital switch matrix may be applied to either the receiver or transmitter components of an advanced multi-band, multi-channel digital transceiver system, and is compatible with routing of signals with different clock frequencies simultaneously within the same switch matrix.

Abstract: Spin-orbital quantum cellular automata logic devices and integrated circuits in the form of a substrate having a thin film of material on the substrate having strongly coupled spin-orbital states, the thin film being patterned to define at least one input and at least one output, and to perform at least one logic operation by associated arrangement of the spin-orbital states between the input and the output. The logic devices and integrated circuits further include an input device at each input to define the spin-orbital states at each input, and an output sensor at each output for sensing the spin-orbital states of the thin film at the output. In an integrated circuit, the output of one gate or circuit, in the form of the ferromagnetically aligned spins, can be directly coupled to the next gate or circuit, so that entire circuits can be fabricated and effectively interconnected, only requiring interfacing for overall.

Abstract: An on-chip current regulator for a superconducting logic circuit isolates the superconducting logic circuit from external noise, reduces the effects of process fluctuations on the performance of the logic circuit and significantly reduces total circuit power requirements. The on-chip current regulator in accordance with the present invention includes one or more hysteretic Josephson junctions each connected in parallel with a resistor forming a resistively shunted junction (RSJ) or includes a self-shunting junction. One RSJ may be coupled between an off-chip current regulator and the hysteretic Josephson junction that functions as a current limiting resistor and provides improved isolation from external noise.

Abstract: A superconducting self-clocked complementary SFQ logic family. The basic element of the circuit is a plurality of Josephson junctions and a control inductance coupled across a pair of voltage rails. An important aspect of the invention relates to the use of voltage biasing for the Josephson junctions, which provides several benefits. First, voltage biasing eliminates the need for biasing resistors as used in constant current mode devices. Such biasing resistors are known to be the dominant source of power dissipation in such logic circuits. Elimination of the biasing resistors thus reduce the power dissipation to the lowest possible value to that of the power dissipation of the switching devices themselves. In addition, the voltage biasing takes advantage of the voltage to frequency relationship of Josephson junctions and automatically establishes a global clock at the Josephson frequency without the need for extra circuitry; thus increasing the practical clock rate.

Abstract: A rapid single-flux-quantum RSFQ logic circuit includes a first circuit portion having a first end grounded and having in-series connected first and second Josephson junctions. A second circuit portion has a first end grounded and has in-series connected third and fourth Josephson junctions. A first inductance element connects a second end of the first circuit portion to a second end of the second circuit portion. A tap is provided in the first inductance element, an input current signal being supplied to the tap. A bias current source is connected to a first connection node between the first and second Josephson junctions. A second inductance element connects the first connection node to a second connection node between the third and fourth Josephson junctions. A superconducting quantum interference device has fifth and sixth Josephson junctions and is coupled to the second inductance element through a magnetic field.

Abstract: An integrated circuit comprises plural superconducting circuit blocks connected through superconducting wiring strips, and each superconducting circuit block includes at least one superconducting logic circuit, constant input/output circuits connected between the input/output nodes of the circuit block and the superconducting logic circuit; parameters of the constant input/output circuits are regulated such that statically flow-in/flow-out current is approximately equal to zero at the input/output nodes of the superconducting logic circuit, whereby the superconducting logic circuit operates at the optimum operating point after the integration.

Abstract: An asynchronous SFQ logic cell that is amenable to being used in combinational logic circuits. Rather than encode each digital logic bit as one SFQ pulse, each logic bit is encoded as a series of SFQ pulses. As such, merge and join circuits can be used for elementary logic cells to form asynchronous combinational logic circuits in accordance with the present invention. Such circuits are relatively faster and denser as well as more compatible with existing synchronous SFQ logic circuits.

Abstract: The invention provides a universal, delay-insensitive RSFQ logic cell comprising two input circuits and two clock circuits, each containing a plurality of Josephson elements. The two input circuits generate and sustain persistent currents in response to input currents. The first clock circuit is arranged to be in electrical contact with the first input circuit such that a portion of the SFQ persistent current from the input circuit combines with an SFQ pulse, generated in the clock circuit, to trigger the generation of a SFQ output pulse. The second clock circuit and the second input circuit are connected in a similar manner. The first input circuit is arranged to be in electrical contact with the second input circuit so that a portion of their SFQ currents combine and trigger the generation of a SFQ output pulse. The universal logic cell can be configured to perform various digital/logical functions.

Abstract: In a superconductive single flux quantum logic circuit having two superconductive closed loops each comprising a Josephson junction and one or more inductors, a load inductance part is comprised of an inductor and a Josephson junction and two or more means for supplying a signal current are included. The load inductance part is made by one or more inductors and means for applying flux via the inductors is included.

Abstract: A superconducting circuit device of a voltage-type logic device is large in current driving capability and, accordingly, electric power consumption; however, the switching speed is not so fast, and a superconducting circuit device of a fluxoid-type logic device is small in current driving capability and, accordingly, the electric power consumption; however the switching speed is faster than that of the superconducting circuit device of the voltage-type logic device, wherein the superconducting circuit device of the voltage-type logic device and the superconducting circuit device of the fluxoid-type logic device are selectively used in a superconducting circuit such as a superconducting random access memory, a superconducting NOR circuit and a superconducting signal converting circuit so as to realize small electric power consumption and high-speed switching action.