Coherent THz electromagnetic radiation emission as a shock wave diagnostic and probe of ultrafast phase transformations

Conference · Tue Jun 30 00:00:00 EDT 2009

DOI:https://doi.org/10.1063/1.3295222· OSTI ID:963525

Reed, E J; Armstrong, M R; Kim, K Y; Glownia, J H; Howard, M; Piner, E; Roberts, J

We present the first experimental observations of terahertz frequency radiation emitted when a terahertz frequency acoustic wave propagates past an interface between materials of differing piezoelectric coefficients. We show that this fundamentally new phenomenon can be used to probe structural properties of thin films. Then, we present molecular dynamics simulations showing that detectable THz frequency radiation can be emitted when a wurtzite structure crystal transforms to a rocksalt structure under shock compression on picosecond timescales. We show that information about the kinetics of the transformation is contained in the time-dependence of the THz field.

• Research Organization: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 963525
• Report Number(s): LLNL-CONF-414924; TRN: US0903369
• Resource Relation: Conference: Presented at: APS Shock Compression of Condensed Matter, Nashville, TN, United States, Jun 28 - Jul 03, 2009
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUMM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ACOUSTICS
COMPRESSION
ELECTROMAGNETIC RADIATION
KINETICS
PHASE TRANSFORMATIONS
PROBES
RADIATIONS
SHOCK WAVES
THIN FILMS
TIME DEPENDENCE
TRANSFORMATIONS