On the energy saved by interlayer interactions in the superconducting state of cuprates

TL;DR

This paper introduces a Ginzburg-Landau-like model to quantify energy savings from interlayer interactions in high-Tc cuprates, linking theoretical mechanisms to experimental data and challenging the significance of the ILT mechanism in certain materials.

Contribution

It proposes a functional capturing interlayer energy effects in high-Tc superconductors and relates these to measurable quantities, providing a framework to evaluate different superconducting mechanisms.

Findings

Interlayer interactions contribute to energy savings in cuprates.

The model suggests minimal Tc increase from ILT in optimally-doped Bi-2212.

Comparison with data supports the model's relevance to experimental observations.

Abstract

A Ginzburg-Landau-like functional is proposed reproducing the main low-energy features of various possible high-Tc superconducting mechanisms involving energy savings due to interlayer interactions. The functional may be used to relate these savings to experimental quantities. Two examples are given, involving the mean-field specific heat jump at Tc and the superconducting fluctuations above Tc. Comparison with existing data suggests, e.g., that the increase of Tc due to the so-called interlayer tunneling (ILT) mechanism of interlayer kinetic-energy savings is negligible in optimally-doped Bi-2212.