Physics – Condensed Matter – Superconductivity
Scientific paper
2000-09-28
Phys.Rev.B63:184519,2001
Physics
Condensed Matter
Superconductivity
12 pages, 8 figures, ReVTeX 3.1
Scientific paper
10.1103/PhysRevB.63.184519
In this paper we demonstrate how, using a natural generalization of BCS theory, superconducting phase coherence manifests itself in phase insensitive measurements, when there is a smooth evolution of the excitation gap \Delta from above to below Tc. In this context, we address the underdoped cuprates. Our premise is that just as Fermi liquid theory is failing above Tc, BCS theory is failing below. The order parameter \Delta_{sc} is different from the excitation gap \Delta. Equivalently there is a (pseudo)gap in the excitation spectrum above Tc which is also present in the underlying normal state of the superconducting phase, and can be directly inferred from specific heat and vortex core experiments. At the same time many features of BCS theory, e.g., fermionic quasiparticles below Tc, are clearly present. These observations can be reconciled by a natural extension of BCS theory, which includes finite center-of-mass momentum pair excitations, in addition to the usual fermionic quasiparticles. Applying this theory we find that the Bose condensation of Cooper pairs, which is reflected in \Delta_{sc}, leads to sharp peaks in the spectral function once $T \le T_c$. These are manifested in ARPES spectra as well as in specific heat jumps, which become more like the behavior in a \lambda transition as the pseudogap develops. We end with a discussion of tunneling experiments and condensation energy issues. Comparison between theoretical and experimental plots of C_v, and of tunneling and vortex core spectroscopy measurements is good.
Chen Qijin
Kosztin Ioan
Levin Kathryn
No associations
LandOfFree
Superconducting phase coherence in the presence of a pseudogap: Relation to specific heat, tunneling and vortex core spectroscopies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Superconducting phase coherence in the presence of a pseudogap: Relation to specific heat, tunneling and vortex core spectroscopies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Superconducting phase coherence in the presence of a pseudogap: Relation to specific heat, tunneling and vortex core spectroscopies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-651254