USA As Represented by Secretary of the Navy

Kenneth L Davis

Carmine Vittoria

Kwo R Chu

Achintya K Ganguly

Denis C Webb

Vincent J Folen

A solid-state cyclotron maser for generating low power (1 watt or less) signals in the submillimeter frequency range (300 GHz-30,000 GHz) includes an accelerating region, a drift region, and a metal grid therebetween. Both regions are formed from semiconductor material, such as indium antimonide, having non-parabolic energy bands. The drift region is a thin disc having metallized outer surfaces, but includes an annular opening in the metal on the front side and a circular opening in the metal on the back side, and is grounded. A grid of metal rings is placed on the annular opening of the drift region. The accelerating region is a hollow cylinder having a metallized front surface. It couples to the drift region for covering the annular opening and the grid. A negative bias voltage is applied to the accelerating region and a magnetic field is applied to the maser at an angle to the axis of the maser. Electrons propagate in spiral trajectories through the accelerating region, grid and drift region. Movement of electrons within the non-parabolic energy bands of the semiconductor material causes changes in the effective mass of the electrons. Phase-bunching of electrons occurs and electrons radiate coherently. Energy is removed from the drift region at the opening on its back side.

Solid-state cyclotron maser

A planar, silicon barrier, Josephson junction and method of forming the junction which does not require expensive high-resolution, lithography techniques such as electron beam or x-ray. The method includes an etching mask-etch process which forms the basic structure configuration using a (110)-cut silicon wafer. Subsequent to the etching process the mask is removed and a superconducting film is deposited on the previously formed silicon surface to produce a single crystal silicon barrier with good electrical properties.

Silicon barrier Josephson junction configuration

A planar, silicon barrier, Josephson junction and method of forming the jtion which does not require expensive high-resolution, lithography techniques such as electron beam or x-ray. The method includes an etching mask-etch process which forms the basic structure configuration using a (110)-cut silicon wafer. Subsequent to the etching process the mask is removed and a superconducting film is deposited on the previously formed silicon surface to produce a single crystal silicon barrier with good electrical properties.

A surface acoustic wave device having a thin magnetostrictive film deposi on the surface between its input and output transducers. A variable D.C. field is applied to the film to vary its characteristics and thereby correspondingly continuously vary the delay or phase shift of the surface acoustic wave.

Magnetically tuned, surface acoustic wave device

An improved optical storage device capable of storing optical images in a charge pattern in a high-resistivity piezoelectric semiconductor layer on a semiconductor substrate. A semiconductor substrate, coated with a layer of electrically insulating material, has a layer of high-resistivity piezoelectric semiconductor covering the insulating layer and covered by a semitransparent biasing electrode. When a negative bias is applied to the electrode, and an optical pattern applied through the electrode, slow states are charged in a short interval to store, for long periods, a pattern imaged by the light. The optical pattern can then be read by using acoustic surface wave imaging techniques to provide electrical imaging of the stored optical pattern.

Semiconductor visible image storage device

An electrically variable surface acoustic wave phase shifter including a strate upon which a piezoelectric layer is deposited and separated therefrom by an insulating layer. An electrode is deposited on the piezoelectric layer and on the bottom of the substrate with an electrical dc bias applied onto the electrodes which causes a charge accumulation or a depletion region at the silicon surface. This charge accumulation or depletion region causes the boundary conditions to change therefore causing a phase change in an acoustical wave propagating along the layered silicon surface.

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Alexandria, VA, United States of America

Kenneth L Davis