Provided is a magnetic sensor testing device capable of preventing performance of an electromagnet from greatly changing due to heat applied to a magnetic sensor. A magnetic sensor testing device includes electromagnets 50 and 60 that apply a magnetic field to a magnetic sensor, temperature regulators 30 and 40 that regulate a temperature of the magnetic sensor by locally applying heat to the magnetic sensor, and a controller that controls the electromagnets 50 and 60 and the temperature regulators 30 and 40, in which the controller tests the magnetic sensor in a state in which the magnetic field is applied to the magnetic sensor by the electromagnets 50 and 60 while the heat is applied to the magnetic sensor by the temperature regulators 30 and 40.

A circuit includes a Superconducting Quantum Interference Array (SQIF), a bias circuit, and a coil. The SQIF generates an output voltage that is a transfer function of the magnetic flux perpendicularly passing through the SQIF. An external magnetic field and a bias magnetic field supply the magnetic flux. The bias circuit generates a bias current for biasing the SQIF at an operating point. The coil generates the bias magnetic field through the SQIF from the bias current of the bias circuit. The bias magnetic field provides nullifying feedback to the SQIF that counterbalances a low-frequency portion of the external magnetic field, such that the output voltage of the SQIF detects a high-frequency portion of the external magnetic field. The circuit can be a receiver with the output voltage of the SQIF detecting an electromagnetic signal while the receiver is moving with changing orientation relative to the Earth's magnetic field.

An information acquisition method includes: executing a voxel defining process to divide an area in which a signal source is assumed to be present and define a voxel division V1 specifying resolution of an image; executing a data collecting process to acquire magnetic field data resulting from measurement of a magnetic field generated in the area; and executing a reconstructing process to estimate, by using a mathematical algorithm, a direction and strength of a current of a signal source at a location of each voxel based on the acquired magnetic field data. The reconstructing process includes: calculating a Gram matrix by using a voxel division V2 defined coarser than the voxel division V1; and reconstructing, by using the Gram matrix, a direction and strength of a current of a signal source in the voxel division V1.

A quantum interference device includes a superconducting loop interrupted by a gap, a plurality of normal conductor segments bridging the gap; and an interferometer connected to the normal conductor segments, wherein the normal conductor segments are spaced apart. There may be 2N+1 normal conductor segments, where N is a positive integer, which may be of equal length and evenly spaced. The device produces a larger signal than a conventional quantum interference device.

A quantum interference device includes a superconducting loop interrupted by a gap, a plurality of normal conductor segments bridging the gap; and an interferometer connected to the normal conductor segments, wherein the normal conductor segments are spaced apart. There may be 2N+1 normal conductor segments, where N is a positive integer, which may be of equal length and evenly spaced. The device produces a larger signal than a conventional quantum interference device.

The present disclosure relates to Superfluid QUantum Interference Devices (SQUIDs) that measure phase differences existing in quasi-particles or matter-wave systems, and the related techniques for their use at room-temperatures. These Bose-Einstein Condensation interferometry techniques include quantum scale metrology devices such as quasi-particle based linear accelerometers, gyroscopes, and Inertial Measurement Units that incorporate such interferometers. In the presence of additive white Gaussian noise, estimates are made for the Bias Instability, Angle Random Walk, and Velocity Random Walk of the device for purposes of quantum inertial sensing. Moreover, this disclosure relates to SQUIDs based on charged quasi-particles that can, in turn, be used to construct quantum computing elements such as quantum transistors, and quasi-particle circuits at room-temperatures. These quasi-particle circuits can be used to build analogs of electronic circuit elements, and offer an alternative to traditional electronics. Using a quasi-particle circuit, hysteresis can be achieved and controlled to build these new devices.

A superconducting quantum interference device (SQUID) for mobile magnetic sensing applications comprising: at least two Josephson junction electrically connected to a superconducting loop; and a resistive element connected in series with one of the Josephson junctions in the superconducting loop. The resistive element is disposed in the same superconducting loop as the at least two Josephson junctions.

A circuit includes a Superconducting Quantum Interference Array (SQIF), a bias circuit, and a coil. The SQIF generates an output voltage that is a transfer function of the magnetic flux perpendicularly passing through the SQIF. An external magnetic field and a bias magnetic field supply the magnetic flux. The bias circuit generates a bias current for biasing the SQIF at an operating point. The coil generates the bias magnetic field through the SQIF from the bias current of the bias circuit. The bias magnetic field provides nullifying feedback to the SQIF that counterbalances a low-frequency portion of the external magnetic field, such that the output voltage of the SQIF detects a high-frequency portion of the external magnetic field. The circuit can be a receiver with the output voltage of the SQIF detecting an electromagnetic signal while the receiver is moving with changing orientation relative to the Earth's magnetic field.

One example includes a tunable current-mirror qubit. The qubit includes a plurality of flux tunable elements disposed in a circuit loop. A first portion of the flux tunable elements can be configured to receive a first input flux and a remaining portion of the flux tunable elements can be configured to receive a second input flux to control a mode of the tunable current-mirror qubit between a microwave excitation mode to facilitate excitation or quantum state manipulation of the tunable current-mirror qubit via a microwave input signal and a noise-protected mode to facilitate storage of the quantum state of the tunable current-mirror qubit. The qubit also includes at least one capacitor interconnecting nodes between respective pairs of the flux tunable elements to facilitate formation of Cooper-pair excitons in each of the microwave excitation mode and the noise-protected mode.

A superconducting quantum interference device (SQUID) for mobile applications comprising: a superconducting flux transformer having a pickup coil and an input coil, wherein the input coil is inductively coupled to a Josephson junction; a resistive element connected in series between the pickup coil and the input coil so as to function as a high pass filter such that direct current (DC) bias current is prevented from flowing through the input coil; and a flux bias circuit electrically connected in parallel to the superconducting flux transformer between the pickup coil and the input coil so as to reduce motion-induced noise.