---------- DTRA ----------

13 Phase I Selections from the 10.2 Solicitation

(In Topic Number Order)
Surface Treatment Technologies, Inc.
1954 Halethorpe Farms Road Suite 600
Halethorpe, MD 21227
Phone:
PI:
Topic#:
(410) 242-0530
Timothy J. Langan
DTRA 102-001      Awarded: 4/1/2011
Title:Tag, Track, and Locate (TTL) technologies and concepts for combating weapons of mass destruction (CWMD).
Abstract:Expand the state-of-the-art to develop new technologies that predict our enemy’s intentions before they act by focusing on “24x7” TTL of terrorists and WMD-related activities in what is now a global theater of war. Enhance technical capabilities to globally tag, track and locate personnel and materials associated with the development, manufacture, or proliferation of WMD. DESCRIPTION: DTRA is seeking TTL technologies that can be used to locate and track either personnel or material associated with WMD-related activities. Personnel applications seek to tag, track, and locate known and suspected WMD terrorists, research scientists, or potential proliferators. TTL technologies will support confirmation of suspected involvement in WMD-related activities; location of WMD research, manufacture, storage, or proliferation sites; and identification of proliferation activities. Material applications seek to tag, track, and locate nuclear materials, biological or chemical agents and their precursors, and WMD employment devices and their spare parts or key supplies. Relevant TTL technologies will support tracking of WMD material, verify locations of friendly or neutral WMD material, confirm locations of suspected WMD supplies, and identify potential WMD proliferation. Ideal TTL tags would possess operating lifetimes measured in months to years. Tag detection and location could come from short-range (1-10 meters) when object movement is constrained to a limited number of well-defined routes (such as roads or building exits) or from long-range (space-based) when object motion is unconstrained. TTL technologies of interest that could be applied to either personnel or material include but are not limited to: 1) Miniature low-power (long lifetime) radio frequency (RF) tags that could be covertly attached to WMD-related personnel or equipment. 2) Novel technologies that enable passive location of RF tags inside structures. 3) Novel materials that change observable characteristics, such as becoming fluorescent, when exposed to radiation associated with WMD-related special nuclear material. 4) Novel materials that could be applied to human hair, skin or other materials, via special lotions, soaps, or shampoos, to provide a persistent signature, and their corresponding detectors. 5) Novel chemical sprays with highly specific signatures that could be applied to WMD- related material, and their corresponding chemical detection systems. 6) Novel nano-materials that could be applied to personnel, equipment, or material that would exhibit laser-induced fluorescence when illuminated by a specific frequency optical or infrared laser. 7) Miniature tags that respond when illuminated by a laser that has been modulated with a specific laser pulse code. 8) Miniature low-power chemical or biological agent detectors that can be integrated with

ventana research
16 North Camino Miramonte
Tucson, AZ 85716
Phone:
PI:
Topic#:
(520) 882-8772
John L. Lombardi
DTRA 102-002      Awarded: 6/27/2011
Title:Weapon Payloads for Chemical and Biological Agent Plume Neutralization
Abstract:To provide new and innovative weapon payload concepts that can neutralize (e.g., detoxify, kill or decompose) chemical and biological (CB) warfare agents in a plume released from an offensive operations strike on enemy Weapons of Mass Destruction (WMD) facilities. DESCRIPTION: Current conventional weapons rely on blast, fragmentation, and heat as their primary mechanism to defeat targets containing CB agents. Unfortunately, these same mechanisms can create large and unacceptable consequences through the release of hazardous and toxic materials into the environment typically as a vented downwind plume. Research of WMD defeat payloads have typically focused on neutralization of CB agents inside target structures prior to venting. However, the risk remains that live CB agent may escape from the targeted structure. An additional capability is necessary that will continue to neutralize CB agents after escaping from a target. This prolonged effect would help further mitigate collateral effects. This type of capability is envisioned to be a singularly deployed subsystem integrated with existing and future conventional and WMD defeat weapons. It would have self-sustaining neutralization characteristics able to travel with aerosolized CB agent escaping outside of the targeted structure, and neutralize the agent as it travels in the contiguous plume. This type of capability is envisioned to reduce the viable CB agent survival fraction by more than an order of magnitude while operating in time-frames of several minutes. Potential solutions may include, but are not limited to, thermal or chemical reactive materials, photo-catalyzed systems, and other conventional munition technologies that are effective against a wide variety of CB agents and sufficiently robust to survive an explosive environment. Solutions should avoid or minimize the creation of toxic degradation products, be safe to store and handle and easily integrated into weapon systems. PHASE I: Perform analysis and research to demonstrate the feasibility of the innovative technology to neutralize CB agents in vented plumes. Any modeling and simulation studies will address the neutralization performance against agents released from all types of CB agent targets that range from mobile launcher to metal buildings and hardened bunkers. The design concept should be benchmarked with data that validates the underlying assumptions and neutralization technologies. The Phase I final report must clearly describe the Phase I to Phase II decision point along with a roadmap of key events through the planned Phase III. PHASE II: Develop and demonstrate a prototype payload capable of neutralizing CB agents/simulants within plumes emanating from offensive operation attacks.. The final Phase II report will include an evaluation of weapon system integration risks and mitigating factors.

General Sciences, Incorporated
205 Schoolhouse Road
Souderton, PA 18964
Phone:
PI:
Topic#:
(215) 723-8588
Peter Zavitsanos
DTRA 102-002      Awarded: 7/21/2011
Title:Weapon Payloads for Chemical and Biological Agent Plume Neutralization
Abstract:To provide new and innovative weapon payload concepts that can neutralize (e.g., detoxify, kill or decompose) chemical and biological (CB) warfare agents in a plume released from an offensive operations strike on enemy Weapons of Mass Destruction (WMD) facilities. DESCRIPTION: Current conventional weapons rely on blast, fragmentation, and heat as their primary mechanism to defeat targets containing CB agents. Unfortunately, these same mechanisms can create large and unacceptable consequences through the release of hazardous and toxic materials into the environment typically as a vented downwind plume. Research of WMD defeat payloads have typically focused on neutralization of CB agents inside target structures prior to venting. However, the risk remains that live CB agent may escape from the targeted structure. An additional capability is necessary that will continue to neutralize CB agents after escaping from a target. This prolonged effect would help further mitigate collateral effects. This type of capability is envisioned to be a singularly deployed subsystem integrated with existing and future conventional and WMD defeat weapons. It would have self-sustaining neutralization characteristics able to travel with aerosolized CB agent escaping outside of the targeted structure, and neutralize the agent as it travels in the contiguous plume. This type of capability is envisioned to reduce the viable CB agent survival fraction by more than an order of magnitude while operating in time-frames of several minutes. Potential solutions may include, but are not limited to, thermal or chemical reactive materials, photo-catalyzed systems, and other conventional munition technologies that are effective against a wide variety of CB agents and sufficiently robust to survive an explosive environment. Solutions should avoid or minimize the creation of toxic degradation products, be safe to store and handle and easily integrated into weapon systems. PHASE I: Perform analysis and research to demonstrate the feasibility of the innovative technology to neutralize CB agents in vented plumes. Any modeling and simulation studies will address the neutralization performance against agents released from all types of CB agent targets that range from mobile launcher to metal buildings and hardened bunkers. The design concept should be benchmarked with data that validates the underlying assumptions and neutralization technologies. The Phase I final report must clearly describe the Phase I to Phase II decision point along with a roadmap of key events through the planned Phase III. PHASE II: Develop and demonstrate a prototype payload capable of neutralizing CB agents/simulants within plumes emanating from offensive operation attacks.. The final Phase II report will include an evaluation of weapon system integration risks and mitigating factors.

Karagozian and Case
2550 North Hollywood Way Suite 500
Burbank, CA 91505
Phone:
PI:
Topic#:
(818) 240-1919
Hyung-Jin Choi
DTRA 102-003      Awarded: 4/13/2011
Title:Stochastic Consideration of Cased Munitions for Casing Breakup and Airblast
Abstract:To develop an analytic method to predict fragment characterization and the resulting airblast propagation from the detonation of a cased explosive. Current procedures are heuristic, based on empirical analysis of test data and simplified analytic expressions. While these work satisfactorily for traditional munitions that detonate in conditions similar to the testing arenas, there is considerable uncertainty for new types of munitions and/or munitions that are partially embedded at detonation. The intent of this effort is to provide an innovative physics-based alternative, using explosive, casing, and environmental properties to produce stochastic fragmentation and airblast load. DESCRIPTION: Casing breakup fragmentation is a phenomenon that is not well analyzed by deterministic approaches such as conventional finite element method because of their randomly distributed characteristics. As a result, a number of heuristic methods based on observations have arisen for characterizing the fragments produced by the casing’s breakup. These methods need to be revisited and upgraded because present day problems related to the detonation of embedded munitions, the increasing use of small precise munitions, and the practice of more precise targeting has given rise to the need for better tools to characterize casing fragments and fragment effects. Since the characterization of fragments and their impact on the behavior of structural components struck by them is an important aspect of characterizing target response, it is important that the present stochastic methodologies (e.g., the Mott equation) and other simplified equations associated with fragment loadings be revised or replaced to reflect the present day problems. Equally important and apparently steeped in even more uncertainty are the methods used to develop the airblast resulting from the detonation of cased munitions. The present reliance on the uncertainties in using the Fano equation, especially for smaller and embedded munitions, needs to be addressed. The present methodology for the generation of fragment and airblast loadings to assess the response of structural components struck relies on relatively simplistic equations to calculate the fragment masses, their distribution, and other properties. Similarly, the Fano equation is generally used to determine the amount of explosive available for airblast generation. In both situations, improvements are warranted. The current assumption for characterizing casing fragments and their application as loading of a structural component is that the fragments are ejected at monotonically increasing angles from the warhead axis as the point of ejection moves from the nose end to

KCF Technologies, Inc
112 W. Foster Ave Suite 1
State College, PA 16801
Phone:
PI:
Topic#:
(814) 867-4009
Michael Grissom
DTRA 102-004      Awarded: 7/12/2011
Title:Energy Harvesting Technologies
Abstract:To provide innovative technologies and system components which increase the lifetime and utility of various systems within DTRA’s Tag, Track, and Locate (TTL) portfolio to combat weapons of mass destruction (WMD). The specific innovations sought under this topic are improved technologies that advance the state of the art for energy scavenging or capture from the ambient environment and high energy density storage. DESCRIPTION: DTRA’s TTL systems are built from an extensible architecture and are designed to enhance the observable signatures of personnel and objects associated with the development, production, storage, or use of Weapons of Mass Destruction. TTL subsystems may include sensors to detect chemical, biological, or nuclear weapons materials or their precursors, and may include radio transmitters to broadcast data such as sensor detections and tag location. A single transmission of tag location information currently requires approximately 4 milli-Joules of energy, and operation of a typical chemical sensor for four minutes can consume an additional 3 milli-Joules. These rates of energy usage consume the energy stored within two commercial lithium batteries (CR123) in approximately two days while it is desirable for TTL systems to endure for weeks or months. Increasing the lifetime of the TTL systems can be accomplished through a combination of active power management, and capturing energy present within the TTL system’s deployment environment. The continuous collection of several micro-Watts of power would yield enough energy to operate a TTL tag transmitter and sensor for a few minutes each hour. Several technologies exist to extract energy from the environment. Reference 1 discusses photovoltaic technologies developed through the Department of Energy’s Solar Energy Technologies Program, and reference 2 is a review article that discusses technologies suitable for recovering energy from mechanical vibrations. Energy harvesting technologies will develop power sub-systems that will enhance the persistence of TTL systems by both capturing and storing ambient energy. Energy harvesting technologies of interest include: • Energy capture: 1) High efficiency photovoltaic cells 2) Micro electromechanical machines (MEMS) electromagnetic generators to harvest mechanical vibration energy 3) Piezoelectric materials to harvest mechanical vibration energy 4) Rectifier-antenna (rectenna) systems to harvest electromagnetic energy • Energy Storage: 1) Small, high-energy density batteries 2) Small, high-energy density capacitors

Radiation Monitoring Devices, Inc.
44 Hunt Street
Watertown, MA 02472
Phone:
PI:
Topic#:
(617) 668-6943
Noa M. Rensing
DTRA 102-004      Awarded: 7/21/2011
Title:Enhanced Beta-Batteries: A Long Life Power Source for Sensors Monitoring WMD Materials
Abstract:To provide innovative technologies and system components which increase the lifetime and utility of various systems within DTRA’s Tag, Track, and Locate (TTL) portfolio to combat weapons of mass destruction (WMD). The specific innovations sought under this topic are improved technologies that advance the state of the art for energy scavenging or capture from the ambient environment and high energy density storage. DESCRIPTION: DTRA’s TTL systems are built from an extensible architecture and are designed to enhance the observable signatures of personnel and objects associated with the development, production, storage, or use of Weapons of Mass Destruction. TTL subsystems may include sensors to detect chemical, biological, or nuclear weapons materials or their precursors, and may include radio transmitters to broadcast data such as sensor detections and tag location. A single transmission of tag location information currently requires approximately 4 milli-Joules of energy, and operation of a typical chemical sensor for four minutes can consume an additional 3 milli-Joules. These rates of energy usage consume the energy stored within two commercial lithium batteries (CR123) in approximately two days while it is desirable for TTL systems to endure for weeks or months. Increasing the lifetime of the TTL systems can be accomplished through a combination of active power management, and capturing energy present within the TTL system’s deployment environment. The continuous collection of several micro-Watts of power would yield enough energy to operate a TTL tag transmitter and sensor for a few minutes each hour. Several technologies exist to extract energy from the environment. Reference 1 discusses photovoltaic technologies developed through the Department of Energy’s Solar Energy Technologies Program, and reference 2 is a review article that discusses technologies suitable for recovering energy from mechanical vibrations. Energy harvesting technologies will develop power sub-systems that will enhance the persistence of TTL systems by both capturing and storing ambient energy. Energy harvesting technologies of interest include: • Energy capture: 1) High efficiency photovoltaic cells 2) Micro electromechanical machines (MEMS) electromagnetic generators to harvest mechanical vibration energy 3) Piezoelectric materials to harvest mechanical vibration energy 4) Rectifier-antenna (rectenna) systems to harvest electromagnetic energy • Energy Storage: 1) Small, high-energy density batteries 2) Small, high-energy density capacitors

Lynntech, Inc.
7610 Eastmark Drive
College Station, TX 77840
Phone:
PI:
Topic#:
(979) 693-0017
Waheguru Singh
DTRA 102-006      Awarded: 6/15/2011
Title:Remote Sensing of CWAs Using Smart Polymers and RFID Readout
Abstract:Develop a prototype sub-millimeter material or material system that responds specifically to a threat stimulus (e.g. chemical, biological, radiological), without the need for an active power source. The response should be instantaneous and readily detectable upon remote electromagnetic (EM) interrogation and must operate in a wide spectrum of environmental conditions (e.g., humidity and temperature) experienced by the Warfighter. An example for consideration is a microelectromechanical/nanoelectromechanical system (MEMS/NEMS)-style device that actuates/activates upon becoming triggered to complete the circuit or deploy a micro-antenna for passive radio frequency identification (RFID) circuit that can be remotely interrogated. DESCRIPTION: Fabrication of MEMS/NEMS devices is quite developed and highly sophisticated; however, fabrication of “smart” material/material systems remains a challenge. The problem at these smaller size scales is portable power to sustain device functionality; power densities of current energy sources prevent the dramatic miniaturization of the overall system. As an alternative, there is a need to develop classes of materials that can respond to a stimulus without any active power sources attached or integrated into the device. Significant research has been conducted to address the development of smart materials which have properties that experience significant, controlled-manner changes upon exposure to an external stimulus; these materials can be inorganic and/or organic, but must meet the criteria listed in the objective. References 1 and 2 are example proof-of- concepts that are analogous to aspects of the desired system, albeit limited in scope/implementation and applicable to aqueous systems. PHASE I: Phase I will culminate in the demonstration of a proof-of-concept millimeter-scale system that is specifically sensitive to one class of threat (chemical, biological or radiological), with characterization of the system response under various environmental and threat concentration conditions. PHASE II: Phase II will involve the development of a family of multiple sub-millimeter scale systems that are specifically sensitive to multiple classes of threat (chemical, biological, or radiological). The systems must have the ability to be remotely interrogated to ascertain status of the sensing element, and a method should exist to differentiate the condition state of each sensor in situations where multiple sensors are implemented. PHASE III DUAL USE APPLICATIONS: Leveraging MEMS/NEMS fabrication strategies enables inexpensive, mass-producible devices that should have strong commercial potential. Inexpensive, incongruous Tag, Track, and Locate (TTL) systems that are reactive to a particular situation, such as food quality, would be of interest to commercial sector

Parabon NanoLabs, Inc.
11260 Roger Bacon Drive Suite 406
Reston, VA 20190
Phone:
PI:
Topic#:
(703) 689-9689
Steven Armentrout
DTRA 102-007      Awarded: 4/1/2011
Title:SNAPSHOT: A System for Predicting Human Physical Traits from Sample DNA
Abstract:OBJECTIVE: Develop a Forensic DNA Analysis Kit for Genetic Intelligence that can be used on unknown human DNA samples collected from the battlefield to provide information about the individual who deposited the sample, such as potential ethnicity, height, eye color, hair color, age, sex, and/or facial features. The kit should leverage Short Tandem Repeats (STR), Single Nucleotide Polymorphisms (SNP), mitochondrial DNA, or next generation sequencing technology. It should also be able to operate on existing commercial technology platforms. DESCRIPTION: Human forensic DNA analysis is routinely performed on materials of interest collected from incident sites or swabs obtained from known individuals. This analysis typically uses commercially available Polymerase Chain Reaction (PCR) kits to generate a DNA profile for the purposes of matching that DNA profile against another DNA profile to establish a potential connection or identity. Forensic DNA analysis has the ability to provide crucial information on individuals who may have built or had contact with IED’s or other potential Weapons of Mass Destruction (WMD). The ability to match an unknown DNA profile obtained from post blast IEDs and objects/containers involved in WMD activities can provide significant insight into who may have manufactured or transported the device, and what agents it may contain. If one is unable to match a DNA profile against an existing database to determine identity, then generating intelligence from this unknown DNA sample has tremendous probative value. The ability to determine the potential ethnicity, height, eye color, hair color, age, sex or facial features from this unknown human DNA profile can be used by commanders and warfighters to increase their situational awareness and enhance their battle management capabilities. The end product should be a Forensic DNA Analysis Kit that includes all critical reagents and operating procedures/methodologies required to generate genetic intelligence information such as, but not limited to, potential ethnicity, height, eye color, hair color, age, sex or facial features that can provide probative information on the potential source of the genetic material. The kit may use Short Tandem Repeats (STR), Single Nucleotide Polymorphisms (SNP), mitochondrial DNA, or next generation sequencing technology and must be able to operate on existing commercial technology platforms. The kit may be used by existing forensic DNA analysis laboratories. Current technologies such as liquid handlers, thermal cyclers, and genetic analyzers/sequencers provide the hardware/technology platform required to process genetic material however a comprehensive genetic intelligence marker and reagent kit that can be run on this platform has yet to be developed. A kit that contains all critical reagents and allows testing for numerous different genetic intelligence markers that is easily integrated

Robust Chip Inc.
7901 Stoneridge Drive Suite 226
Pleasanton, CA 94588
Phone:
PI:
Topic#:
(925) 425-0820
Klas Lilja
DTRA 102-008      Awarded: 6/2/2011
Title:Solutions for Single-Event Effects in Ultra Deep Submicron Semiconductor Technologies Using Simulation and Layout Techniques
Abstract:The successful outcome of this effort will support the use of ultra-deep submicron integrated circuits in DoD satellite systems that will result in very significant savings in weight, power and reliability for systems that include Space Radar, Space Tracking and Surveillance Systems and others. In addition, this effort will also support the use of compound semiconductor technologies (e.g. antimony based compound semiconductors, indium phosphide, and others) in these systems and their introduction into advanced spacecraft and missile systems with similar savings in both power and weight, coupled with increased performance. DESCRIPTION: Current satellite systems are fabricated using a mix of commercial and radiation hardened circuits. However, the use of advanced commercial integrated circuits devices results in added complexity to mitigate radiation effects that can result in the mis- operation and/or destruction of devices. In many cases, the penalties in increased power, area, weight and added circuit complexity out-weigh any potential benefits and preclude the use of the advanced commercial technology. Moreover, these technologies have demonstrated sensitivity to radiation effects. The present methods to mitigate radiation effects, while proven to be effective at circuit geometries > 150nm silicon based technology, have been shown to be less effective when applied to integrated circuit feature sizes below 100nm silicon based and compound semiconductor technologies. In addition, the introduction of new technologies, e.g. quantum function circuits, will require the development of new mitigation approaches. Thus, if minimally invasive methods such as the use of alternative materials, circuit enhancements, and other innovative approaches could be developed to reduce radiation effects sensitivity these devices could be used with little or no penalties. Therefore, the basic approach to accomplish this task would be to leverage commercial microelectronics at the < 90nm nodes and augment these technologies with radiation mitigation techniques that would have minimal impact on the electrical performance and manufacturability. This same approach also applies to the radiation hardening of the compound semiconductor and other technologies. Additionally, the development of such methods requires the development of cost effective methods to model and simulate the radiation response of these < 90nm, compound semiconductor and other technologies. Without a robust modeling and simulation capability it would be both technically and economically unfeasible to develop these mitigation methods.

Orora Design Technologies, Inc.
18378 Redmond Fall City Road
Redmond, WA 98052
Phone:
PI:
Topic#:
(425) 702-9196
Lili Zhou
DTRA 102-008      Awarded: 4/19/2011
Title:The Characterization and Mitigation of Radiation Effects on Nano-technology Microelectronics
Abstract:The successful outcome of this effort will support the use of ultra-deep submicron integrated circuits in DoD satellite systems that will result in very significant savings in weight, power and reliability for systems that include Space Radar, Space Tracking and Surveillance Systems and others. In addition, this effort will also support the use of compound semiconductor technologies (e.g. antimony based compound semiconductors, indium phosphide, and others) in these systems and their introduction into advanced spacecraft and missile systems with similar savings in both power and weight, coupled with increased performance. DESCRIPTION: Current satellite systems are fabricated using a mix of commercial and radiation hardened circuits. However, the use of advanced commercial integrated circuits devices results in added complexity to mitigate radiation effects that can result in the mis- operation and/or destruction of devices. In many cases, the penalties in increased power, area, weight and added circuit complexity out-weigh any potential benefits and preclude the use of the advanced commercial technology. Moreover, these technologies have demonstrated sensitivity to radiation effects. The present methods to mitigate radiation effects, while proven to be effective at circuit geometries > 150nm silicon based technology, have been shown to be less effective when applied to integrated circuit feature sizes below 100nm silicon based and compound semiconductor technologies. In addition, the introduction of new technologies, e.g. quantum function circuits, will require the development of new mitigation approaches. Thus, if minimally invasive methods such as the use of alternative materials, circuit enhancements, and other innovative approaches could be developed to reduce radiation effects sensitivity these devices could be used with little or no penalties. Therefore, the basic approach to accomplish this task would be to leverage commercial microelectronics at the < 90nm nodes and augment these technologies with radiation mitigation techniques that would have minimal impact on the electrical performance and manufacturability. This same approach also applies to the radiation hardening of the compound semiconductor and other technologies. Additionally, the development of such methods requires the development of cost effective methods to model and simulate the radiation response of these < 90nm, compound semiconductor and other technologies. Without a robust modeling and simulation capability it would be both technically and economically unfeasible to develop these mitigation methods.

Applied Physical Electronics, L.C.
PO Box 341149
Austin, TX 78734
Phone:
PI:
Topic#:
(512) 264-1804
W. Clay Nunnally
DTRA 102-010      Awarded: 6/15/2011
Title:Research in Photoconductive Semiconductor Switching (PCSS)
Abstract:Advanced pulsed power switching technologies are needed to enable future nuclear weapon effects (NWE) experimentation capabilities and concepts for the active interrogation of special nuclear materials (SNM). The objective of this research is to advance the state of the art of high-gain optically-triggered switches by increasing the current density (to >1000 A/cm) and voltage hold-off (>67 kV/cm and >100 kV total) capabilities of complete switch assemblies that allow simple laser illumination, function in oil immersion, and have rise-times and timing jitter <0.3 ns. DESCRIPTION: Traditional pulsed power systems have primarily used spark gaps in various forms as the main switches for high voltage (>100 kV) and high current (>100 kA) operations. Spark gap switches have limitations in terms of their triggering requirements, timing jitter and turn on time (both typically greater than a few nanoseconds). Photoconductive Semiconductor Switches (PCSS) are one method of switching high voltages without requiring direct electrically-connected trigger systems. PCSS have been demonstrated using silicon carbide (SiC), gallium nitride (GaN), and semi-insulating gallium arsenide (GaAs) for voltages over 100 kV with turn on times of 0.35 ns and timing jitter of ~0.1 ns. Unlike most semiconductors that only conduct as long as they are illuminated by enough light to generate current carriers, GaAs PCSS have the advantage of also being high-gain; once the device is turned on by a short laser pulse, they can remain conducting through a stable electron avalanche process. The primary issue with GaAs PCSS is that the current becomes filamentary with channel widths of ~50 micrometers and that the current per filament must be limited to <25 A for short pulses (<100 ns) in order to have long lifetimes (>107 shots). This limit is set by the localized heating of the conducting channel and the need to keep the temperature below the melting point. If bulk GaAs is uniformly illuminated, the current tends to form a few, high- current channels that can damage the switch. Illuminating with narrow lines of laser light bridging the switching gap and spaced ~300 micrometers apart has been shown to allow multiple parallel channels to form and remain separate. However, this requirement limits the overall current density and makes the laser triggering optics more complex and/or inefficient. Research in this topic areas may address : (1) The development of techniques such as “dead-bands” between channels to prevent transverse current flow and the merging of neighboring channels. It may be possible to achieve this through ion implantation or other means. If the spacing of channels can be reduced to ~100 micrometers, the current density could be tripled. (2) The development of integrated focusing lens assemblies that work under transformer oil,

UES, Inc.
4401 Dayton-Xenia Road
Dayton, OH 45432
Phone:
PI:
Topic#:
(937) 426-6900
Rabi S. Bhattacharya
DTRA 102-010      Awarded: 7/18/2011
Title:Development of Photoconductive Semiconductor Switch
Abstract:Advanced pulsed power switching technologies are needed to enable future nuclear weapon effects (NWE) experimentation capabilities and concepts for the active interrogation of special nuclear materials (SNM). The objective of this research is to advance the state of the art of high-gain optically-triggered switches by increasing the current density (to >1000 A/cm) and voltage hold-off (>67 kV/cm and >100 kV total) capabilities of complete switch assemblies that allow simple laser illumination, function in oil immersion, and have rise-times and timing jitter <0.3 ns. DESCRIPTION: Traditional pulsed power systems have primarily used spark gaps in various forms as the main switches for high voltage (>100 kV) and high current (>100 kA) operations. Spark gap switches have limitations in terms of their triggering requirements, timing jitter and turn on time (both typically greater than a few nanoseconds). Photoconductive Semiconductor Switches (PCSS) are one method of switching high voltages without requiring direct electrically-connected trigger systems. PCSS have been demonstrated using silicon carbide (SiC), gallium nitride (GaN), and semi-insulating gallium arsenide (GaAs) for voltages over 100 kV with turn on times of 0.35 ns and timing jitter of ~0.1 ns. Unlike most semiconductors that only conduct as long as they are illuminated by enough light to generate current carriers, GaAs PCSS have the advantage of also being high-gain; once the device is turned on by a short laser pulse, they can remain conducting through a stable electron avalanche process. The primary issue with GaAs PCSS is that the current becomes filamentary with channel widths of ~50 micrometers and that the current per filament must be limited to <25 A for short pulses (<100 ns) in order to have long lifetimes (>107 shots). This limit is set by the localized heating of the conducting channel and the need to keep the temperature below the melting point. If bulk GaAs is uniformly illuminated, the current tends to form a few, high- current channels that can damage the switch. Illuminating with narrow lines of laser light bridging the switching gap and spaced ~300 micrometers apart has been shown to allow multiple parallel channels to form and remain separate. However, this requirement limits the overall current density and makes the laser triggering optics more complex and/or inefficient. Research in this topic areas may address : (1) The development of techniques such as “dead-bands” between channels to prevent transverse current flow and the merging of neighboring channels. It may be possible to achieve this through ion implantation or other means. If the spacing of channels can be reduced to ~100 micrometers, the current density could be tripled. (2) The development of integrated focusing lens assemblies that work under transformer oil,

Srico, Inc.
2724 SAWBURY BOULEVARD
COLUMBUS, OH 43235
Phone:
PI:
Topic#:
(614) 799-0664
Vincent Stenger
DTRA 102-011      Awarded: 6/21/2011
Title:Omnidirectional Photonic Electric Field Sensor for Diagnosing Nuclear Weapons Effects
Abstract:To develop novel diagnostics to improve the accuracy of both test environment and test object response measurements during nuclear weapons effects (NWE) experiments. Improved diagnostic accuracy is needed to reduce the overall uncertainties in response models and design margins in support of the system certification and hardness surveillance processes. DESCRIPTION: The development and sustainment of military systems that must operate in environments that have been disturbed by nuclear weapons requires a detailed understanding of the responses of all components of the system to all aspects of the threat environment. The environments and responses of concern here include: thermal through vacuum ultra-violet radiation; prompt x-rays; prompt and delayed gamma rays and neutrons; pumped electron radiation belts; electromagnetic pulse (EMP); Source Region EMP (SREMP); System Generated EMP (SGEMP); Box Internal EMP (IEMP); Transient Radiation Effects in Electronics (TREE); and Thermomechanical Effects (TME), including Thermostructural Response (TSR), Thermomechanical Shock (TMS), optical surface modification, and blow-off impulse. SGEMP and IEMP experiments in particular require the use of compact, non-perturbing D- dot and B-dot sensors to measure the local electric and magnetic fields that are induced by x-ray generated electron currents. Additionally, TME experiments need better diagnostics for localized stress, strain, and displacement in high radiation environments. The ability to model the performance of many pulsed-power driven radiation sources depends on knowing the voltages and currents reaching the load regions. The vacuum power transmission lines typically used have very harsh radiation, plasma and electron current environments that make measurements of average electric and magnetic fields difficult. Novel vacuum power flow diagnostics are needed to measure magnetic fields of 105-107 Gauss and electric fields of 107-109 Volts/meter with time resolution of nanoseconds. More accurate (< 5% uncertainty) diagnostics are needed of the dose, dose-rate, and spectrum of pulsed x-rays used in many NWE radiation experiments. In particular, accurate spectral diagnostics are needed for x-rays below 3 keV and for the 15-200 keV range. To be considered for funding, the proposed concepts must be shown to potentially lead to practical, affordable diagnostics that will result in reduced overall uncertainties in the critical parameters associated with a NWE experiment for component response or model validation.