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Isotope power supplies offer long-lived (100 years using 63 Ni), low-power energy sources, enabling sensors or communications nodes for the lifetime of infrastructure. A tritium beta-source (12.5-year half-life) encapsulated in a phosphor-lined vial couples directly to a photovoltaic (PV) to generate a trickle current into an electrical load. An inexpensive design is described using commercial-of-the-shelf (COTS) components that generate 100 W e for next-generation compact electronics/sensors. A matched radiation sensor has been built for long-duration missions utilizing microprocessor-controlled sleep modes, low-power electronic components, and a passive interrupt driven environmental wake-up. The low-power early-warning radiation detector network and isotope power source enables no-maintenance mission lifetimes. Keywords: isotope power sources, low illumi nation PV, low-power electronics 1. INTRODUCTION The size of personal electrical devices is continually shrinking. Unfortunately, the power requirements of sensors, compact communications equipment, and light sources are not shrinking as fast as device size and weight. This paradox of compact size, yet greater energy consumption is not sustai nable. Chemical batteries ar e the inexpensive mainstay of power for these devices; however, chemical batteries have limited lifetimes (

A tritium-based indirect converting photovoltaic (PV) power source has been designed and prototyped as a long-lived (~15 years) power source for sensor networks. Tritium is a biologically benign beta emitter and low-cost isotope acquired from commercial vendors for this purpose. The power source combines tritium encapsulated with a radioluminescent phosphor coupled to a commercial PV cell. The tritium, phosphor, and PV components are packaged inside a BA5590-style military-model enclosure. The package has been approved by the nuclear regulatory commission (NRC) for use by DOD. The power source is designed to produce 100μW electrical power for an unattended radiation sensor (scintillator and avalanche photodiode) that can detect a 20 μCi source of 137Cs at three meters. This beta emitting indirect photon conversion design is presented as step towards the development of practical, logistically acceptable, lowcost long-lived compact power sources for unattended sensor applications in battlefield awareness and environmental detection.

Isotope batteries offer solutions for long-lived low-power sensor requirements. Alpha emitting isotopes have energy per decay 103 times that of beta emitters. Alpha particles are absorbed within 20 mm of most materials reducing shielding mitigation. However, damage to materials from the alphas limits their practical use. A Schottky Barrier Diode (SBD) geometry is considered with an alpha emitting contact-layer on a diamond-like crystal semiconductor region. The radiation tolerance of diamond, the safety of alpha particles, combined with the internal field of the SBD is expected to generate current useful for low-power electronic devices over decades. Device design parameters and calculations of the expected current are described.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

This paper reviews the experimental research accomplished to date relating to catastrophic electromagnetic breakdown in certain media that are interesting for high voltage, short temporal pulse width pulsers. The authors begin with the classic work of Felsenthal and Proud and follow experimental results into the present day. The paper considers not only the experimental results of short pulse radio frequency breakdown but also the relationship with long pulse RF breakdown. The paper presents some recent measurements as well as reviewing the previous work performed in our laboratories and elsewhere.

Recent advances in theoretical and experimental research concerned with the feasibility of the gamma-ray laser are reviewed. The discussion covers the principal concepts, pump calibration, giant pumping resonances, and the development of a laser model. A quantitative model based on new data and concepts demonstrates the feasibility of the gamma-ray laser.