Condensation energy in the spin-fermion model for cuprates
نویسنده
چکیده
We compute the condensation energy in the spin-fermion model using Scalapino-White relation between the condensation energy and the change in the dynamical structure factor in the normal and the superconducting states. We show that for parameters relevant to cuprates, the extra low-frequency spectral weight associated with the resonance peak in the dynamical structure factor in a superconductor is not compensated up to energies ;J which are much larger than the superconducting gap D . We argue that in this situation, the condensation energy is large and well accounts for the data for cuprates.
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