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I'm interested in many-body phenomena in condensed matter, particularly in liquids and glasses. I'm currently working on a model that will hopefully explain the low temperature universalities in amorphous solids. 

 Non-technical Description:

Any solid that does not have long range order is called an amorphous solid. All non-metallic objects in the room you sit in right now (including you) are most likely amorphous solids. The opposite of amorphous is "crystalline".

The atoms in a solid jiggle back and forth and these jigglings form sound waves. At low temperatures the typical wavelength of such vibrations tend to be much longer than the spacing between atoms, therefore one would expect that acoustic properties do not depend much on how the atoms are arranged.

But they do: The acoustic properties of an amorphous solid are completely different than that of a crystal. One observes extra degrees of freedom even at extremely low temperatures when everything is expected to sit dead-still. Furthermore, an amorphous solid responds very strangely to sound: If you poke an amorphous solid once, nothing will happen. But if you poke it twice, it will poke you back.

Not only are amorphous solids unexpectedly different from crystals, they're also unexpectedly similar among themselves - to which one refers as "universality" -. For example, a sound wave will always travel as much as 150 times it's own wavelength, regardless of the chemical composition or bonds.

 

Publications

Molecular-Dynamics Simulations of Carbon Nano-Cage Structures: Nanoballs and Nanotoroids Int. J. of Mod. Phys. C, Vol. 12, No. 5 (2001) 685-690

Counting Objects with Biologically Inspired Regulatory-Feedback Networks International Joint Conference on Neural Networks (IJCNN09), in press

 

Dervis Vural

Dervis Can Vural