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       COLLOQUIUM OF THE LABORATORY FOR COMPUTER DESIGN OF MATERIALS
           Institute for Computational Sciences and Informatics
				  CSI 929
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    Interband Sign Reversal of the Superconducting Order Parameter: 
            General Theory and Implication for Cuprates

			     Igor Mazim
 Complex Systems Theory Branch, Naval Research Laboratory, Washington D.C.


One of the key questions in the problem of the high-Tc superconductivity
is pairing symmetry. There is strong evidence that the superconducting state
in high-Tc cuprates is highly anisotropic; the superconducting
order parameter seems to be changing not only magnitude, but also its sign,
over the Fermi surface. An example of such a state is the state where the
order parameter has angular dependence as an l=2 angular harmonic (so-called
d-wave pairing). I will report a quanitative (numerical) study of
another possible highly anisotropic superconducting state, where the order
parameter has different signs in different bands.

                      Monday , March 31, 1997
                               4:30 pm
                    Room 206, Science & Tech. I
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