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The performance of a current-voltage (I-V) dc programmable Josephson voltage standard (PJVS) operating on a commercially available Gifford-McMahon cryocooler at 4 K is examined. Results suggest the generation of voltage steps of over 1 V with quantum precision.

Research describing a superconducting quantum interference device ammeter based on subranging architecture is presented. In particular a two range digital device with fine and coarse resolution channels is developed.

A study was conducted on a single-chip digital superconducting quantum interference device (SQUID) magnetometer. Results show that an input analog SQUID determines the noise level and sensitivity in an optimized magnetometer chip. The chips can be used in high magnetic field environments without extensive magnetic shielding due to their wide dynamic range. External two-phase clock frequencies were used to determine the devices' slew rate.

An integrated digital superconducting quantum interference device (SQUID) magnetometer is fabricated by using a single chip as a platform for a SQUID-based pre-amplifier, a high sensitivity comparator gate and feedback circuitries. The magnetometer has a very wide dynamic range and is capable of operating in unshielded environments. It slew rate can be significantly improved by adding Josephson junction-based counters for a faster clock rate.

A single-chip SQUID magnetometer achieves a wider dynamic range with a smaller feedback coil. This chip can be used in unshielded environments and allows on-chip multiplying. The chip makes the operation with bidirectional counter feasible. The superconducting line's current carrying capacity limits the dynamic range.

An analog to digital converter (ADC), based on niobium nitride (NbN) technology, was manufactured by employing a tight-layer NbN-based mechanism with a Josephson function critical current density of 500 A per squared cm. The NbN-based ADC chip operates at 9.5 K and has linearity and high resolution.