Re: ASA Member in the News

An electrically neutral excited state of an insulator or semiconductor,
often regarded as a bound state of an electron and a hole. Electrons and
holes are the negaive and positive charge carriers in a semiconductor.
Exiton is an "exotic atom" in that the coulomb-correlated pairs are not the
normal protons and electrons but other entitites. Other exotic atoms include
positronium (electron/positron pairs) and my personal favorite, strange
matter (strange quarks bound together with an electron "atmosphere") which
is theorized to be in massive neutron stars.

On 6/21/05, Charles Carrigan <CCarriga@olivet.edu> wrote:
>
> anyone care to fill me in on what an "exciton" is?
> C
> <><<><<><<><<><<><<><<><<><<><<><<><
> Charles W. Carrigan, Ph.D.
> Olivet Nazarene University
> Dept. of Geology
> One University Ave.
> Bourbonnais, IL 60914
> PH: (815) 939-5346
> FX: (815) 939-5071
>
>
> >>> Jack Haas <haas.john@comcast.net> 06/21/05 10:48 AM >>>
>
> ASA member David Snoke in the news.
>
>
> Physical Review Letters
> Pitt and Bell Labs researchers send 'heavy photons' over world-record
> distances <
> http://www.eurekalert.org/pub_releases/2005-06/uop-pab062105.php>
> Scientists from the University of Pittsburgh and Bell Labs report that
> they have designed and demonstrated a two-dimensional semiconductor
> structure in which excitons exist longer and travel farther than
> previously recorded.* David Snoke,* a senior author and an associate
> professor of physics and astronomy at Pitt, and his colleagues report a
> system in which excitons move freely over distances of hundreds of
> microns. Their findings open up the possibility of new applications,
> such as excitonic circuits.
>
Received on Tue Jun 21 16:15:32 2005