Kinetic energy change with doping upon superfluid condensation in high temperature superconductors

G. Deutscher; A. F. Santander-Syro; N. Bontemps

doi:10.1103/physrevb.72.092504

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Kinetic energy change with doping upon superfluid condensation in high temperature superconductors

G. Deutscher·A. F. Santander-Syro·N. Bontemps

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Abstract

In conventional BCS superconductors, the electronic kinetic energy increases upon superfluid condensation (the change DEkin is positive). Here we show that in the high critical temperature superconductor Bi-2212, DEkin crosses over from a fully compatible conventional BCS behavior (DEkin>0) to an unconventional behavior (DEkin<0) as the free carrier density decreases. If a single mechanism is responsible for superconductivity across the whole phase diagram of high critical temperature superconductors, this mechanism should allow for a smooth transition between such two regimes around optimal doping.

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G. Deutscher, A. F. Santander-Syro, N. Bontemps. 2005-03-03. Kinetic energy change with doping upon superfluid condensation in high temperature superconductors. https://doi.org/10.1103/physrevb.72.092504

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