Prof. Thomas S. Duffy visits HPSTAR

Prof. Thomas S. Duffy from the department of Geosciences at Princeton University,  visited HPSTAR from Aug. 8 to Aug.11, 2016. Duffy's research focuses on understanding the large-scale physical and chemical behavior of the Earth and other planets through experimental study of geological materials under extreme conditions of pressure and temperature.

During his visit at HPSTAR, Prof. Duffy delivered a  talk on the development of  dynamic high pressure technology in recent years and some prelimnary results of their very recent research. Dynamic compression is  another important loading method relative to static high pressure technique-diamond anvil cell. Dynamic compression studies have wide-ranging applications to problems in Earth and planetary science ranging from the effects of impacts and explosions to the synthesis of new phases.

He  discussed two major new advances in the field of dynamic compression in the talk.

Firstly, prof. dufft introduced Laser-based dynamic compression. "The laser-based dynamic compression (Ramp) has provided us opportunities to study the structures and properties of geological materials to ultrahigh pressure conditions reaching 1 terapascal and beyond", said prof. duffy. " By controlling the shape and duration of the incident laser pulse, either shock or ramp (shockless) loading can be produced. By combining these techniques with pulsed x-ray diffraction, we have explored a variety of materials including iron silicide, magnesium oxide, and carbon to ultrahigh pressures relevant to exoplanet interior conditions".

Then he introduced another the development at the Dynamic Compression Sector at the Advanced Photon Source which provides the capability to couple gas-gun shock-wave experiments with brilliant synchrotron X-rays.  

Prof. Duffy also showed some preliminary results on the lattice-level structural response of quartz and fused silica under shock loading.