A thrust stand was modified, and a primary calibration technique was developed to evaluate the performance of applied-field pulsed magnetoplasmadynamic thrusters (MPDTs) for 10 kW class solar electric orbit transfer vehicle (SEOTV) missions. The NASA Lewis Research Center (LeRC) 30 kW thrust stand was modified to accept high current pulses delivered to the MPDT. A pendulum system was developed ...

A new approach for the electro-thermal modeling of LDMOSFETs for power-amplifier design that bypasses pulsed-IVs and pulsed-RF measurements is presented in this paper. The existence of low-frequency dispersion in LDMOSFETs is demonstrated by comparing pulsed IVs with iso-thermal IVs. The modeling technique uses iso-thermal IV and microwave measurements to obtain the temperature dependence of sm...

The resonant pumping of holmium fibre lasers provides a fibre laser platform capable of addressing a wide range of applications that benefit from operation at wavelengths beyond 2.1 μm. This architecture can provide laser devices that promise high efficiency sources in the 2.1 μm spectral region with excellent beam quality and power scalability. This paper presents our recent results of resonan...

The goal of the LAGUNA experimental series of the Los Alamos National Laboratory TRAILMASTER program is to accelerate an annular aluminum plasma z-pinch to greater than one hundred kilojoules of implosion kinetic energy. To accomplish this, an electrical pulse )5.5 MA must be delivered to a 20 nH load in ~1 ~s. The pulsed power system for these experiments consists of a capacitor bank for initi...

A wire-array flux-compression cartridge installed on Sandia's Saturn pulsed power generator doubled the current into a 3-nH load to 6 MA and halved its rise time to 100 ns. The current into the load, however, was unexpectedly delayed by almost 1 micros. Estimates of a plasma flow switch acting as a long-conduction-time opening switch are consistent with key features of the power compression. Th...

In this paper, a model of a railxun is developed and ~ used to illustrate a d&harge event on an energy storage capacitor. This rallgun model is designed to operate at a power level compatible with the Naval Combat Survivability testbed. The rallgun simulation model is Incorporated Into the NCS pulsed power charging circuit models. Simulations are perfonned showing the charglnx circuits charging...

Large-mode-area double clad fibers offer excellent efficiency and beam quality, high output power as well as lightweight, robust and reliable packaging. The addition of polarization maintaining property though use of well-know Panda-structure has further increased the interest in double clad fibers, especially in fibers doped with ytterbium (Yb). Many material processing, military and R&D appli...

A compact UV pulsed laser pumped by high-power two-dimensional arrays of vertical-cavity surface-emitting lasers (VCSELs) was presented. A passively Q-switched 1064-nm Nd:YAG laser was side-pumped by kW-class 808-nm VCSEL pump modules and the output pulses were frequency quadrupled to 266-nm. 10-ns, 0.68-mJ UV pulsed output was obtained at 1.33k-Hz repetition rate. The average UV power is > 0.9...

In a specially designed radiation force balance (RFB), low-frequency pulse modulation of the incident ultrasound allows high-accuracy measurement of time-averaged spatially-integrated ultrasound power radiated into a reflectionless water load. Errors characteristic of force sensors are precluded by operating the RFB as a force comparator, without directly measuring force. Equipped with purpose-...