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The invention uses the superconducting "proximity effect" and/or the "inverse proximity effect" to form a spatially varying order parameter. When designed to expel magnetic flux from a region of space, the proximity effect(s) are used in concert to make the superconducting order parameter strongly superconducting in the center and more weakly superconducting toward the perimeter. The shield is then passively cooled through the superconducting transition temperature. The superconductivity first nucleates in the center of the shielding body and expels the field from that small central region by the Meissner effect. As the sample is further cooled the region of superconducting order grows, and as it grows it sweeps the magnetic flux lines outward.

Electronic waveforms exist that exceed the capabilities of state-of-the-art data acquisition hardware that is commonly available. The electronic waveforms that need to be measured simultaneously contain wide bandwidth, high frequency content, a DC reference, high dynamic range, and a high crest factor. The NASA Glenn high-speed data acquisition system creates a voltage compression effect with a custom transfer function that is adapted to the voltage range, frequency bandwidth, and electrical impedance of both the test article and data acquisition device. The compression transfer function is later reversed (or decompressed) with a software algorithm to restore the original signal's voltage from the acquired data. The data is thus improved via better signal-to-noise ratio, better low-amplitude accuracy, better resolution, and preservation of high-frequency spectral content. The circuit can be realized with either passive components or both active and passive components. Either realization is specialized for the test article and data acquisition hardware. This is an early-stage technology requiring additional development. Glenn welcomes co-development opportunities.

The gated chopper integrators function is to amplify low level signals without introducing excessive offset and noise and to do this with accurate and variable gain. The unique feature of the technology is the inherent demodulation present in the integrator which eliminates the need for filtering and allows the user to accurately vary the gain in finely graduated steps. The reduction of the offset of the amplifier is very efficient and lends itself to radiation hardened by design implementations. Since total dose can change the offset due to varying threshold voltages of CMOS transistors, the circuit adapts and compensates for any variations. The autozero integrator also adapts to its own varying offsets. The net outcome is variable, accurate gain that is very robust to supply variations, radiation effects and aging. The technology was developed as a multi-channel thermopile signal processor. Lab measurements indicate very accurate amplification with low offset and noise.

To avoid catastrophic failure, traditional electrical ohmic contacts must be placed at some distance from the optimal position (especially for sensors) in high-temperature environments. In addition, conventional metallization techniques incur significant production costs because they require multiple process steps of successive depositions, photolithography, and etchings to deposit the desired ohmic contact material. Glenn's novel production method both produces ohmic contacts that can withstand higher temperatures than ever before (up to 600°C), and permits universal and simultaneous ohmic contacts on n- and p-type surfaces. This makes fabrication much less time-consuming and expensive while also increasing yield. This innovative approach uses a single alloy conductor to form simultaneous ohmic contacts to n- and p-type 4H-SiC semiconductor. The single alloy conductor also forms an effective diffusion barrier against gold and oxygen at temperatures as high as 800°C. Glenn's extraordinary method enables a faster and less costly means of producing SiC-based sensors and other devices that provide quicker response times and more accurate readings for numerous applications, from jet engines to down-hole drilling, and from automotive engines to space exploration.

The uCA combines a high accuracy integrated silicon pressure sensor with MOSFET technology to provide traditional Normally-Open and Normally-Closed switches capable of high power switching for a wide variety of applications. The output of the sensor and switches are provided to the user for real-time altitude determination as well as discrete altitude trip point knowledge. Updates to the altitude trip points are facilitated through USB programming, which allows for in-field adjustment and provides added flexibility late during integration and testing.

Glenn's innovative nanoSSSD device includes a doped semiconducting substrate, an insulating layer deposited on the substrate, an electrode formed on the insulating layer, and at least one polymer nanofiber deposited on the electrode. The deposited nanofiber provides an electrical connection between the electrode and the substrate, serving as the electro-active element in the device. The nanofiber is generally composed of a customized polymer (e.g., polyaniline) that is extremely sensitive to the adsorption and desorption of a single gas molecule. As gas molecules are adsorbed and desorbed, the resistivity of the customized polymer also changes, providing its sensing capacity. When the nanoSSSD device senses a selected gaseous species, the switching portion of the device automatically actuates, sending a signal to the control component. This control component activates the output (warning) device. In addition to its ability to detect harmful gases (including ammonia, hydrogen, hydrocarbons, nitrogen oxides, carbon monoxide, and carbon dioxide), Glenn's device can also feature conducting polymers that are sensitive to UV radiation. Glenn's nanoSSSD technology has great commercial potential, particularly in situations where frequent replacement of the switch/sensor is impractical.

This technology utilizes the U.S. high-voltage power transmission grid system as an extremely large antenna to extract unprecedented spatiotemporal space physical and geological information from distributed GIC observations. GICs are measured using differential a magnetometer technique involving one fluxgate magnetometer under the transmission line and another reference magnetometer station nearby. The reference station allows subtraction of the natural field from the line measurement, leaving only the GIC-related Biot-Savart field. This allows inversion of the GIC amplitude. The magnetometer stations are designed to operate autonomously. They are low-cost, enabling large scale application with a large number of measurement locations.

For fast platform dynamics, it is necessary to sample the IMU at quick intervals in order to fulfill the Nyquist sampling theorem requirements. This can be difficult in cases where low size, weight, and power are required, since a primary processor may already be saturated running the navigation algorithm or other system functions. Glenn's novel circuit board was designed to handle the sampling process (involving frequent interrupt requests) in parallel, while delivering the resulting data to a buffered communication port for inclusion in the navigation algorithm on an as-available basis. The circuit operates using a universal serial bus (USB) or Bluetooth interface. A control command is sent to the circuit from a separate processor or computer that instructs the circuit how to sample data. Then, a one-pulse-per-second signal from a GPS receiver or other reliable time source is sent to trigger the circuit to perform automatic data collection from the IMU sensor. This is an early-stage technology requiring additional development. Glenn welcomes co-development opportunities.

A planar lateral air transistor was fabricated using standard silicon semiconductor processing. The emitter and collector were sub-lithographically separated by photoresist ashing, with the curvature of the tip controlled by the thermal reflow of the photoresist. The gap can be shrunk as small as 10nm using this process. Since the nanogap separating the emitter and collector is smaller than the electron mean free path in air, vacuum is not needed. The present structure exhibits superior gate controllability and negligible gate leakage current due to adoption of the gate insulator. The device has potential for high performance and low power applications; also, since vacuum as the carrier transport medium is immune to high temperature and radiation, the proposed nanotransistors are ideal for extreme environments. Process and layout refinements such as coating a low work function material on the emitter, reducing the overlap area and optimizing the oxide thickness can potentially improve the cut-off frequency well into the THz regime.