Page 200

Coherent Terahertz Acoustic Phonons: A Novel Diagnostic for Erosion in Hall Thruster Discharge Chamber Walls Marshall University Research/NASA Ames Research Center, Kennedy Space Center, Space Technology Mission Directorate

Left to right, Thomas E. Wilson, Ph.D. (Science PI, Department of Physics, Marshall University), and Daniel Crowder (MU Physics Undergraduate student).

The goal of this NASA EPSCoR sponsored research was to develop a novel coherent source of high-frequency sound waves in crystalline solids (the quanta of which are called ‘phonons’) and to use the source as a new approach to performing diagnostic experiments of the erosion of thin-films of hexagonal boron nitride (h-BN) and/or its composites due to xenon ion impact in Hall ion rockets. The ability to generate coherent nanosecond pulses of sub- through terahertz frequency regime acoustic phonons has been a long-standing goal of condensed matter physics. Dr. Wilson’s laboratory is the only one in the world attempting to produce coherent transverse acoustic (shear TA) phonons in the hypersonic sub-terahertz frequency regime by the resonant driving of the alternating space charge layers of MBE-grown superlattices with the electric field of a far-infrared (FIR) laser. The laser radiation is germanium prism-coupled to the superlattice layers and derives from the PI’s novel cavity-dumped, optically-pumped far-infrared molecular gas laser. Interdisciplinary collaborations have been developed between the research team at Marshall University (MU) and researchers from the University of Michigan and Rensselaer Polytechnic Institute (RPI). http://science.marshall.edu/wilsont/lab.html

Left to right, Thomas Wilson, Sarah Barber (MU Chemistry Undergraduate student), Research Associate, Dr. Konstantin A. Korolev (MU Post-Doc Physics).

198

|

NASA EPSCoR Stimuli 2014 -15

Kyle L. Dixon, NASA Technical Monitor, Kennedy Space Center

EPSCoR Stimuli 2014-15  

NASA Office of Education’s Aerospace Research & Career Development (ARCD) is pleased to release NASA EPSCoR Stimuli, a collection of univers...

Read more
Read more
Similar to
Popular now
Just for you