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Evaluates the performance of superconducting thin-film transformers at microwave frequencies. Effects of stray capacitance and nonzero electrical length; Current-voltage characteristics; Transmission line model.

Reports on the designing of circuits to transmit and receive bits generated by Single-Flux-Quantum (SFQ) circuits. Fabrication of the circuits using shunted Nb-AlOx-Nb junctions; Information on the transmitter; Coupling of the receiver circuit to the transmitter.

We have designed and measured single flux quantum (SFQ) circuits for data switching at 2.5 Gbps. A fully functional 2/spl times/2 switching node is presented. The node can be used to form a larger switching fabric (4/spl times/4, 8/spl times/8, etc.). The node accepts data streams at either or both inputs, routing the data based on address bits present in the data stream. This approach allows the data to be self-routing and the switch to be self-synchronous. In addition, the switch can route data correctly on an active input line if the other is idle. [ABSTRACT FROM PUBLISHER]

We have designed circuits to transmit and receive bits generated by Single-Flux-Quantum (SFQ) circuits. Our circuits were fabricated using shunted Nb-AlOx-Nb junctions. The transmitter is a series array of dc SQUIDs driven into the voltage state in response to an input SFQ pulse. The receiver circuit is inductively coupled to the transmitter. Current from the transmitter biases a junction race in the receiver such that a clock pulse either passes (a '1' bit) or does not (a '0' bit). We have measured a maximum peak-to-peak amplitude from the transmitter of 296 /spl mu/V at a clock rate of 2.5 GHz, and 187 /spl mu/V at 5 GHz. [ABSTRACT FROM PUBLISHER]

Evaluates picovoltmeters based on a high transition temperature direct current superconducting quantum interference device (SQUID). Connection of the voltage source to a calibrated resistor and a coil coupled to a SQUID; Components of the coil; Determination of the lowest voltage noise achieved.

Investigates the noise performance of YBa[sub 2]Cu[sub 3]O[sub 7-x] direct current superconducting quantum interference devices (SQUID). Absence of effect in the white noise of the devices at 77 Kelvin; Increase in the magnitude of the spectral density of the 1/f noise; Impact of the increase in noise on SQUID operated in the field of the earth.

Examines the production of magnetic images of eddy currents in patterned copper thin films using a scanning magnetic flux microscope. Use of weak applied fields in small structure imaging; Application of the superconducting quantum interference device in the image production; Induction of eddy currents in the samples.

Details the fabrication of direct current (dc) superconducting quantum interference device (SQUID) magnetometers with single film YBa[sub 2]Cu[sub 3]O[sub 7-x] flux transformers. Attachment of the transformer to a loop directly coupled to a dc SQUID; Values of the lowest magnetic field noise achieved; Applications of the device.

Fabricates the direct current superconducting quantum interference device (SQUID) magnetometers from YBa[sub 2]Cu[sub 3]O[sub 7-x] thin films. Use of flux modulation to measure the magnetometer noise; Relationship between magnetic field sensitivity and hole size; Effect of reducing SQUID inductance on magnetic field resolution.

Describes the fabrication and testing of an integrated thin-film magnetometer with two superconducting layers. Use of superconducting quantum interference device as flux transformer crossunder; Sequence of deposition and photolithographic patterning of the layers; Measurement of magnetic flux and field noise; Use of x-ray diffraction technique.

Evaluates magnetic microscopy through liquid nitrogen cooled YBa[sub 2]Cu[sub 3]O[sub 7] superconducting quantum interference device. Production of two-dimensional images of magnetic fields; Development of magnetic flux microscope; Presentation of magnetic images.

Examines YBa[sub 2]Cu[sub 3]O[sub 7-x] thin film magnetometer. Use of photolithographic processing to pattern layers; Operation of the magnetometer; Determination of the flux transformer critical current; Measurement of the device magnetic field sensitivity.