Sodium germanate glasses in the soda range 14% x 19%, show a glass transitions to be nearly thermall

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Self-Organization in Network GlassesP.Boolchand,
University of Cincinnati, DMR-0456472
Investigations in our laboratory on inorganic
glasses have shown that physical properties, such
as the nature of the glass transition, molar
volumes, vibrational mode frequencies, and
electrical conductivities, change systematically
but in some instances sharply with chemical
composition. In sodium germanate glasses, for
example, (a) glass transitions become thermally
reversing when the soda content increases to the
14 sharp edges (phase boundaries). In this window
glasses show (b) a minimum in molar volumes, and
form networks that are stress-free and do not
age. These features are identified with a new
self-organized phase of disordered matter. The
finding is opening new vistas in basic physics
and applications of disordered materials.
Sodium germanate glasses in the soda range 14
nearly thermally reversing and (b) molar volumes
to reveal a global minimum.
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Self-Organization in Network GlassesP.Boolchand,
University of Cincinnati, DMR-0456472
Education Five graduate students, Ping Chen,
Deassy Novita (female), Mingji Jin (female),
Ninghua Wang and Chad Holbrook are working
towards their Ph.D. Thesis. Four of these
students are supported by this NSF Award.
Pictures of the students, of the facilities and
equipment in the laboratory, recent presentations
and publications are available on
www.ececs.uc.edu/pboolcha/ The site is used by
the PI in teaching courses at UC.
Societal Impact There is growing evidence to
suggest that (i) thin-film gate dielectrics in
standard solid state chips, (ii) window glass
that has shaped science and evolution of
civilization since middle ages, (iii) Protein
structures and reversibility of folding pathways,
(iv) Satisfiability problems in Computer Science,
and (v) Origin of pairing in High-Temp-erature
Superconductors, may owe their functionality to
an underlying self-organized disordered phase.
Phil. Mag. 85, 3823 (2005).
The pink layer at the Si/SiO2 interface of the
gate is self-organized (SO), and chiefly
responsible for sustained operation of typical
solid state chips.