Superconducting fluctuations in the Luther-Emery liquid

Spectral properties of Luther-Emery systems

We calculate the spectral function of the Luther-Emery model which describes one-dimensional fermions with gapless charge and gapped spin degrees of freedom. We find a true singularity with interaction dependent exponents on the gapped spin dispersion and a finite maximum depending on the magnitude of the spin gap, on a shifted charge dispersion. We apply these results to photoemission experime...

Gauge fluctuations in superconducting films

In this paper we consider a type-I superconducting film modeled by the Ginzburg-Landau model, confined between two parallel planes a distance L apart from one another. Our approach is based on the Gaussian effective potential in the transverse unitarity gauge, which allows to treat gauge contributions in a compact form. Using techniques from dimensional and ζ-function regularizations, modified ...

Spin - gap phase in the extended t − J chain

We study the one-dimensional deformed t−t−J model in terms of the continuum field theories. We found that at low doping concentration and far away from the phase separation regime, there are two phases: the Luttinger liquid and the Luther-Emery liquid, depending on t/t < (t′/t)c or t /t > (t′/t)c, where (t′/t)c > 0. Moreover, the singlet superconducting correlations are dominant in the Luther-E...

Fluctuations from edge defects in superconducting resonators

Superconducting resonators, used in astronomy and quantum computation, couple strongly to microscopic two-level defects. We monitor the microwave response of superconducting resonators and observe fluctuations in dissipation and resonance frequency. We present a unified model where the observed dissipative and dispersive effects can be explained as originating from a bath of fluctuating two-lev...

Critical Fluctuations in Normal-to-superconducting Transition