[Physics-mmm] SSO seminar reminder

[Yun-Shik Lee]

Dear all,

This is a reminder of the SSO seminar today. Prof. Lisa Zurk from PSU ECE 
department will talk about her research on THz time-domain spectroscopy. The 
title and abstract is following.

Prof. Lisa Zurk, PSU ECE
Terahertz Time Domain Spectroscopy Scattering Signatures

There has been considerable interest in the potential application of 
terahertz (THz) time domain spectroscopy (TDS) for a variety of problems, 
including the detection of explosive devices and imaging for biomedical 
applications. The THz regime has many advantages, including the possibility 
of a safe (non-ionizing) screening modality and the potential for 
high-resolution 3D imaging. It also has the advantage of exhibiting spectral 
peaks that can be used, for example, to classify explosives or detect the 
presence of cancerous cells. However, in addition to the chemical 
spectroscopic structure, many materials also produce a classic 
electromagnetic scattering response due to the presence of volume scatterers 
and/or rough interfaces present in the object. This response can serve to 
alter or obscure the identifying resonances, and thus it is critical to 
understand the nature of the scattering. In this work, random media models 
are devised to quantify the classical scattering response due to embedded 
volume inhomogeneities (in the form of spherical inclusions) and a rough 
surface interfaces that may occur between dielectric layers. Results are 
presented from THz transmission and reflection measurements of granular 
samples and compared with theoretical results calculated using a 
Quasi-Crystalline Approximation (QCA) and rough surface scattering theory. 
Implications of the scattering signatures and direction for future research 
in the THz area are presented and discussed.

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 Yun-Shik Lee
 Associate Professor

 Department of Physics              Office: 541-737-5057 (415 Weniger Hall)
 Oregon State University            Fax: 541-737-1683
 301 Weniger Hall                      E-mail: leeys at physics.oregonstate.edu
 Corvallis, OR 97331-6507
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