Lawrence Livermore National Security, LLC

US Government As Represented by the Secretary of the Army

Bae Systems Land & Armaments L.p.

Other

University of California

University of Illinois

Socal Simulations, LLC

Lars F Voss

Adam M Conway

Rebecca J Nikolic

Qinghui Shao

Sara Elizabeth Harrison

Clint Frye

Mihail Bora

Robert T Graff

Paulius Vytautas Grivickas

Joseph Devin Schneider

Stephen Anthony Payne

Art J Nelson

Tammy Chang

Caitlin Anne Chapin

Roger A Henderson

Mark A Stoyer

Tiziana C Bond

Mark S Rader

Victor V Khitrov

Chin Li Cheung

John Winter Murphy

Erik Lars Swanberg, Jr

David Lawrence Hall

Catherine E Reinhardt

Luis M Hernandez

Daniel Heineck

John Berns Lancaster

Dongxia Qu

Noah Patrick Allen

Joshua D Kuntz

Stephen E Sampayan

Srabanti Chowdhury

George James Caporaso

Peter M Asbeck

Hoang Tan Nguyen

John Edward Heebner

Michael Charles Rushford

Vincenzo Lordi

Alexander A Baker

Steve Hawkins

Ishwara B Bhat

Hadong Kim

Alexander Peter Povilus

Jinkyu Han

Benjamin J Fasenfest

Joel Varley

Paul O Leisher

Cedric Rocha Leao

Sangtae Park

Devin Joseph Funaro

Kyoung Eun Kweon

Bikramjit Chatterjee

Laura Leos

Aaron J Simon

Mushtaq A Dar

Patrick R Beck

Daniel Max Dryden

Tzu Fang Wang

Ryan P Brisbin

Adam P Conway

Victor P Karpenko

Dawn A Shaughnessy

Jenny Zhou

Karen Marie Dowling

Kexin Li

Allan S Chang

Shaloo Rakheja

Brandon Demory

Devices, methods and techniques related to photoconductive switches using diamond are disclosed. In one example aspect, a photoconductive apparatus includes a diamond layer positioned to receive a light. The diamond layer is doped with nitrogen. The apparatus also includes a first electrode coupled to the diamond layer to provide a first electrical contact for the diamond layer, and a second electrode coupled to the diamond layer to provide a second electrical contact for the diamond layer and configured to reflect the light back to the diamond layer. The first electrode and the second electrode are configured to establish an electric field across the diamond layer in response to receiving the light.

Photoconductive switch with diamond

In one general embodiment, a structure includes a first diode, comprising: a first layer having a first type of dopant, and a second layer above the first layer, the second layer having a second type of dopant that is opposite to the first type of dopant. A second diode is formed directly on the first diode. The second diode comprises a first layer having a third type of dopant and a second layer above the first layer of the second diode, the second layer of the second diode having a fourth type of dopant that is opposite to the third type of dopant. In another general embodiment, a process includes a repeated sequence of growing a first layer having a first type of electrically active dopant and growing a second layer having a second type of electrically active dopant that is opposite to the first type of dopant.

Monolithic growth of epitaxial silicon devices via co-doping

Disclosed are apparatuses and methods of tuning a radio frequency circuit using stub tuners and photoconductive switches. In one aspect an electromagnetic stub tuner apparatus is disclosed. the apparatus includes a transmission line, and a photoconductive switch positioned along the length of the transmission line. The photoconductive switch is configured to turn on or turn off, wherein an impedance of the transmission line is changed when the photoconductive switch is turned on compared to when the photoconductive switch is turned off. In another aspect, a method of tuning a radio frequency circuit is disclosed. In yet another aspect, a method of producing a radio frequency tuning circuit is disclosed.

Photoconductive semiconductor-based stub tuners for high power

A product includes an elongated carbon-containing pillar having a bottom and a tip opposite the bottom. The width of the pillar measured 1 nm below the tip is less than 700 nm. A method includes masking a carbon-containing single crystal for defining masked regions and unmasked regions on the single crystal. The method also includes performing a plasma etch for removing portions of the unmasked regions of the single crystal, thereby defining a pillar in each unmasked region, and performing a chemical etch on the pillars at a temperature between 1200° C. and 1600° C. for selectively reducing a width of each pillar.

Silicon carbide nanoneedles and fabrication thereof

Amorphous silicon carbide may be doped with one or more ions such as vanadium and these ions may radiate light if excited, for example, using optical or electrical pumping. A single photon light source may be formed from a single such ion that is pumped or from a plurality of ions that are pumped if light from only one ion is collected, e.g., using an aperture or pin hole. Such single photon sources may possibly be use in quantum computing, quantum sensing and/or quantum telecommunications.

Doped amorphous silicon carbide

An apparatus includes at least one vertical transistor, where the at least one vertical transistor includes: a substrate including a first semiconductor material, an array of three dimensional (3D) structures above the substrate, a sidewall heterojunction layer positioned on at least one vertical sidewall of each 3D structure, and an isolation region positioned between the 3D structures. Each 3D structure includes the first semiconductor material. The sidewall heterojunction layer includes a second semiconductor material, where the first and second semiconductor material have different bandgaps.

Three dimensional vertically structured electronic devices

An apparatus includes a heterostructure including a substrate of Group-III-nitride material, a source layer including a dopant positioned on a surface of the substrate, and a conductive cap layer positioned on the source layer. A method of electric field-enhanced impurity diffusion includes obtaining a heterostructure including a substrate of Group-III-nitride semiconductor material, a source layer including a dopant positioned directly on the substrate, and a conductive cap layer positioned above the source layer, and applying a thermal annealing treatment to the heterostructure. An electric field gradient is established within the source layer and the cap layer for causing diffusion of an element from the substrate to the cap layer, and for causing diffusion of the dopant from the source layer to a former location of the element in the substrate thereby changing a conductivity and/or magnetic characteristic of the substrate.

Field assisted interfacial diffusion doping through heterostructure design

A high-voltage switch is adapted for use as a medium-voltage direct current circuit breaker, which provides a low-cost, small-footprint device to mitigate system faults. In one example, a method for operating a wideband optical device includes illuminating the wide bandgap optical device with a light within a first range of wavelengths and a first average intensity, allowing a current to propagate therethrough without substantial absorption of the current, illuminating the wide bandgap optical device with light within the first range of wavelengths and a second average intensity that is lower than the first average intensity to allow a sustained current flow though the wide bandgap optical device, and illuminating the wide bandgap optical device with light within a second range of wavelengths to stop or substantially restrict propagation of the current through the wide gap material.

Wide bandgap optical switch circuit breaker for controlling propagation of current therethrough a wide bandgap optical device

An optically addressable light valve comprises a first transparent conductor layer, a layer of liquid crystal, and a photoconductor comprising an ultrawide band gap (UWBG) semiconductor. The liquid crystal is between the first transparent conductor layer and the semiconductor photoconductor. The optically addressable light valve is configured to apply a voltage across the liquid crystal and the UWBG semiconductor. A second transparent conductor may be formed in the UWBG semiconductor in some configurations, and the voltage may be applied across the first and second transparent conductor.

Optically addressable light valves for high power operation

Disclosed are non-linear transmission lines using ferromagnetic materials to generate ferromagnetic resonance oscillations. In one aspect, a non-linear transmission line apparatus is disclosed. The apparatus includes an outer conductor having a first side and a second internally facing side, and an inner conductor positioned internal to the non-linear transmission line apparatus. The apparatus further includes a ferromagnetic material surrounding the inner conductor, wherein the ferromagnetic material comprises nanoparticles of an ε-polymorph of iron oxide expressed as ε-FeO. The apparatus also includes a first dielectric material positioned between the outer conductor and the inner conductor, the dielectric material in contact with both the ferromagnetic material and with the second internally facing side of the outer conductor, wherein the outer conductor, the inner conductor, the dielectric material and the ferromagnetic material form the nonlinear transmission line.

Gyromagnetic nonlinear transmission line for radio frequency signal generation and pulse compression

A high-voltage switch, whose operation leverages the speed of electrons to generate the 'on' time of the pulse in combination with the speed of light to generate the “off” time of the pulse, is described. In one example, the high-voltage switch includes a first electrode, a second electrode spaced apart from the first electrode, a region of non-absorbing material occupying a portion of the space between the first and second electrodes and allowing a laser pulse to propagate therethrough without substantial absorption, and a region of absorbing material occupying another portion of the space and producing a charged particle cloud upon receiving the laser pulse. The high-voltage switch remains “on” upon the charged particle cloud reaching an electrode and until it has been collected by the electrode, and where the high-voltage switch remains “off” subsequent to the collection and until another generated charged particle cloud reaches the electrode.

High-power electrically tunable switch

A photoconductive switch that uses materials that support negative differential mobility, whose operation leverages the pulse compression of a charge could to generate the 'on' time of the pulse in combination with the speed of light to generate the 'off' time of the pulse, is described. In one example, a method of operating a photoconductive switch, which includes two electrodes and a light absorbing material positioned therebetween, includes selecting a value for one or more parameters comprising a voltage for generation of an electric field, a spot size of a laser pulse, a temporal pulse width of the laser pulse, or an intensity of the laser pulse, wherein the selected value(s) for the one or more parameters enable the switch to operate in a region where the light absorbing material exhibits negative differential mobility, and illuminating the light absorbing material with the laser pulse to generate a charge cloud within the light absorbing material.

Pulse compression photoconductive semiconductor switches

Power amplifier apparatuses and techniques for optimizing the design of power amplifiers are disclosed. In one aspect, a method for optimizing a power amplifier includes selecting a circuit topology for the power amplifier. The circuit topology includes one or more photoconductive switches and an impedance matching network including one or more parameter values representative of the impedance matching network or the photoconductive switches that can be adjusted. The method further includes selecting one or more optimization goals for the impedance matching network and the one or more photoconductive switches, and adjusting the one or more parameter values according to the one or more optimization goals. The one or more optimization goals include an efficiency at a particular power output.

High efficiency photoconductive semiconductor switch-based amplifier for high power microwave transmission

In one embodiment, an apparatus includes at least one vertical transistor, where the at least one vertical transistor includes: a substrate comprising a semiconductor material, an array of three dimensional (3D) structures above the substrate, a gate region, and an isolation region positioned between the 3D structures. Each 3D structure includes the semiconductor material. Each 3D structure also includes a first region having a first conductivity type and a second region having a second conductivity type, the second region including a portion of at least one vertical sidewall of the 3D structure. The gate region is present on a portion of an upper surface of the second region and the gate region is coupled to a portion of the at least one vertical sidewall of each 3D structure.

According to one embodiment, a device includes a first electrode, a second electrode spaced from the first electrode, a well extending between the first electrode and the second electrode, one or more chalcogens in the well, and at least one halogen mixed with the one or more chalcogens in the well. In addition, the chalcogens are selected from the group consisting of sulfur, selenium, tellurium, and polonium.

Liquid semiconductor-halogen based electronics

Growing community of inventors

Pleasanton, CA, United States of America

Lars F Voss