Pseudogap and phonon gap. Does phonon (pseudo)gap exist?

[M@2]

We all know that there exist pseudogap in superconductors and in metals (semimetals).

Were there the experiments, aimed to find gaps analogues to pseudogap in phonon spectrum?

Is pseudogap T* is connected with some change in phonon spectrum in some direction?

The same question for superconducting Tc.

 

[ZapperZ]

Why should there be a pseudogap in the phonon spectrum? We know there are no pseudogap in most conventional superconductors.

The pseudogap in present in the spin channel of the cuprates. See NMR experiments on this family of material. So there are indications that this pseudogap could be remnants of the antiferromagnetic background of the parent material.

Zz.