A resolution to doping asymmetry puzzle in high Tc cuprates

G. Baskaran

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A resolution to doping asymmetry puzzle in high Tc cuprates

G. Baskaran

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Abstract

We present a microscopic model for `electron doped' $Nd_{2-x}Ce_xCuO_4$ family and offer a resolution to a long standing doping asymmetry puzzle. Here, i) Ce atoms do not dope free electrons, instead a Ce atom effectively quenches a $Cu^{2+}$ spin moment at an adjacent site, at an energy scale > superexchange J of $CuO_2$ plane and `site dilutes' the Mott insulator. ii) Effective chemical pressure, caused by increased Ce substitution, induces a {\em first order Mott insulator to superconductor transition} in the $CuO_2$ plane. We predict, i) {\em equal number of +e and -e carriers} in metallic state and ii) a line of first order transition ending at a critical point in normal state. Phenomenology gets organized.

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G. Baskaran. 2005-05-23. A resolution to doping asymmetry puzzle in high Tc cuprates. https://arxiv.org/abs/cond-mat/0505509

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