Abstract: A process enables growing thick stoichiometric crystalline and preferably IR-transparent optical PCMO material on Si and other substrates. Sputter deposition is carried out in oxygen-free inert gas (e.g., Ar) environment, which helps to prevent decomposition of the PCMO material over the substrate. In the disclosed process, there is no need to add a seed layer prior to PCMO deposition. Moreover, no post-deposition annealing is needed in a high-temperature and high-pressure oxygen furnace, but an anneal provides certain additional benefits in terms of improved transparency at IR wavelengths. Over a long deposition time for a thick PCMO film on the high temperature (?450° C.) substrates, the PCMO deposition is made repeated cycles of deposition of the PCMO material at the high temperature, each deposition cycle being followed by cooling the PCMO-deposited substrate to a substantially lower temperature (<50° C.).

Abstract: A solid state electrically variable focal length lens includes a plurality of concentric rings of electro-optical material, wherein the electro-optical material comprises any material of a class of hydrogen-doped phase-change metal oxide and wherein each respective concentric ring further includes a transparent resistive sheet on a first face of the respective concentric ring, wherein the transparent resistive sheet extends along the first face, and a first voltage coupled between a first end and a second end of the transparent resistive sheet, wherein the first voltage may be varied to select an optical beam deflection angle.

Abstract: A solid state optical beam steering device including a body of electro-optical material wherein the body of electro-optical material comprises any material of a class of hydrogen-doped phase-change metal oxide and wherein the body has a first face and a second face opposite the first face, a first transparent resistive sheet on the first face of the body of electro optic material, wherein the first transparent resistive sheet has a first side and a second side, and a transparent conductor on the second face of the body of electro optic material, wherein the transparent conductor is coupled to the second side of the first transparent resistive sheet.

Abstract: A vertical directional coupler or switch comprising a lower and an upper waveguide, integrated with an optical phase change material disposed between the lower and upper waveguides to control a directional of optical coupling between the lower and upper waveguides.

Abstract: An optical apparatus may comprise: an electrically reconfigurable optical layer comprising at least one phase-change material, wherein an optical property of the phase-change material is reconfigurable by an electric field; an optically transparent top electrode and a bottom electrode, the top and bottom electrodes configured to apply the electric field to the electrically reconfigurable optical layer, wherein the electrically reconfigurable optical layer is disposed between the optically transparent top electrode and the bottom electrode; and a colossal-K dielectric layer disposed between the electrically reconfigurable optical layer and the bottom electrode. The phase-change material of the electrically reconfigurable optical layer may comprise phase-change nickelate or tungsten oxide. The phase-change material of the electrically reconfigurable optical layer may have a perovskite structure.

Abstract: A HEMT comprising: a substrate; a channel layer coupled to the substrate; a source electrode coupled to the channel layer; a drain electrode coupled to the channel layer; and a gate electrode coupled to the channel layer between the source electrode and the drain electrode; wherein the channel layer comprises: at least a first GaN layer; and a first graded AlGaN layer on the first GaN layer, the Al proportion of the first graded AlGaN layer increasing with the distance from the first GaN layer.

Abstract: A method of fabricating a gate with a mini field plate includes forming a dielectric passivation layer over an epitaxy layer on a substrate, coating the dielectric passivation layer with a first resist layer, etching the first resist layer and the dielectric passivation layer to form a first opening in the dielectric passivation layer, removing the first resist layer; and forming a tri-layer gate having a gate foot in the first opening, the gate foot having a first width, a gate neck extending from the gate foot and extending for a length over the dielectric passivation layer on both sides of the first opening, the gate neck having a second width wider than the first width of the gate foot, and a gate head extending from the gate neck, the gate head having a third width wider than the second width of the gate neck.

Abstract: A method for time interleaved writing includes providing a phase change material (PCM) array, the PCM array comprising a plurality of phase change material areas arranged in a two dimensional array having rows and columns, selecting PCM areas to configure, and configuring the selected PCM areas. Selecting PCM areas to configure includes selecting PCM areas to configure in both the row and column dimensions that are separated by at least two PCM areas that are not selected to be configured.

Abstract: A four-terminal GaN transistor and methods of manufacture, the transistor having source and drain regions and preferably two T-shaped gate electrodes, wherein a stem of one of the two T-shaped gate electrodes is more closely located to the source region than it is to a stem of the other one of the two T-shaped gate electrodes and wherein the stem of the other one of the two T-shaped gate electrodes is more closely located to the drain region than it is to the stem of said one of the two T-shaped gate electrodes. The the gate closer to the source region is a T-gate, and the proximity of the two gates is less than 500 nm from each other. The spacing between the stem of the RF gate and source region and the stem of the DC gate and drain region are preferably defined by self-aligned fabrication techniques. The four-terminal GaN transistor is capable of operation in the W-band (75 to 100 GHz).

Abstract: A transistor includes a substrate, a channel layer coupled to the substrate, a source electrode coupled to the channel layer, a drain electrode coupled to the channel layer, and a gate electrode coupled to the channel layer between the source electrode and the drain electrode. The gate electrode has a length dimension of less than 50 nanometers near the channel layer, and the channel layer includes at least a first GaN layer and a first graded AlGaN layer on the first GaN layer.

Abstract: A method for time interleaved writing includes providing a phase change material (PCM) array, the PCM array comprising a plurality of phase change material areas arranged in a two dimensional array having rows and columns, selecting PCM areas to configure, and configuring the selected PCM areas. Selecting PCM areas to configure includes selecting PCM areas to configure in both the row and column dimensions that are separated by at least two PCM areas that are not selected to be configured.

Abstract: A device including a biopolymer membrane, a passivation layer on the biopolymer membrane, a graphene layer on the passivation layer, a source electrode on the graphene layer, and a drain electrode on the graphene layer, wherein the graphene layer extends between the source electrode and the drain electrode.

Abstract: An optical apparatus may comprise: an electrically reconfigurable optical layer comprising at least one phase-change material, wherein an optical property of the phase-change material is reconfigurable by an electric field; an optically transparent top electrode and a bottom electrode, the top and bottom electrodes configured to apply the electric field to the electrically reconfigurable optical layer, wherein the electrically reconfigurable optical layer is disposed between the optically transparent top electrode and the bottom electrode; and a colossal-K dielectric layer disposed between the electrically reconfigurable optical layer and the bottom electrode. The phase-change material of the electrically reconfigurable optical layer may comprise phase-change nickelate or tungsten oxide. The phase-change material of the electrically reconfigurable optical layer may have a perovskite structure.

Abstract: A transistor includes a substrate, a channel layer coupled to the substrate, a source electrode coupled to the channel layer, a drain electrode coupled to the channel layer, and a gate electrode coupled to the channel layer between the source electrode and the drain electrode. The gate electrode has a length dimension of less than 50 nanometers near the channel layer, and the channel layer includes at least a first GaN layer and a first graded AlGaN layer on the first GaN layer.

Abstract: A photodetector comprising a region of a p-type phase-change chalcogenide material forming a heterojunction with a region of n-type Silicon; wherein the p-type phase-change chalcogenide material comprises one of GeTe and SbTe.

Abstract: A reconfigurable electro-magnetic tile includes a laser layer including a plurality of lasers, and a pixelated surface comprising a plurality of metal patches and a plurality of switches, wherein each respective switch of the plurality of switches is in a gap between a first respective metal patch and a second respective metal patch, wherein each respective switch is optically coupled to at least one respective laser of the plurality of lasers, and wherein each switch of the plurality of switches comprises a phase change material.

Abstract: A photodetector comprising a region of a p-type phase-change chalcogenide material forming a heterojunction with a region of n-type Silicon; wherein the p-type phase-change chalcogenide material comprises one of GeTe and SbTe.

Abstract: A neuroelectric sensor and stimulator system includes a first antenna, a reader coupled to the first antenna for transmitting stimulation controls and power to a second antenna, and for receiving sensor data transmitted from the second antenna via the first antenna, and at least one neuroelectric sensor stimulator array including the second antenna, a rectifier coupled to the second antenna for extracting power transmitted from the first antenna, a controller coupled to the second antenna for decoding controls transmitted from the first antenna to the second antenna for the neuroelectric sensor stimulator array, a plurality of sensors, a multiplexer coupled to the controller and to the plurality of sensors for selecting a single sensor, and a plurality of stimulators coupled to the controller for stimulating neurons, wherein the rectifier, the controller, the plurality of sensors, the multiplexer, and the plurality of stimulators include graphene.

Abstract: A device including a biopolymer membrane, a passivation layer on the biopolymer membrane, a graphene layer on the passivation layer, a source electrode on the graphene layer, and a drain electrode on the graphene layer, wherein the graphene layer extends between the source electrode and the drain electrode.

Abstract: A neuroelectric sensor and stimulator system includes a first antenna, a reader coupled to the first antenna for transmitting stimulation controls and power to a second antenna, and for receiving sensor data transmitted from the second antenna via the first antenna, and at least one neuroelectric sensor stimulator array including the second antenna, a rectifier coupled to the second antenna for extracting power transmitted from the first antenna, a controller coupled to the second antenna for decoding controls transmitted from the first antenna to the second antenna for the neuroelectric sensor stimulator array, a plurality of sensors, a multiplexer coupled to the controller and to the plurality of sensors for selecting a single sensor, and a plurality of stimulators coupled to the controller for stimulating neurons, wherein the rectifier, the controller, the plurality of sensors, the multiplexer, and the plurality of stimulators include graphene.