Dependence of the superconducting effective mass on doping in cuprates

TL;DR

This paper models how the effective mass of paired carriers in cuprates varies with doping, revealing a rapid decrease in underdoped regions and a trend towards Fermi-liquid behavior with increased doping, aligning with experimental observations.

Contribution

It introduces a doping-dependent multiband model spectrum that successfully reproduces key superconducting properties across the doping scale in cuprates.

Findings

Effective mass $m_{ab}$ decreases rapidly in underdoped cuprates.

The $n_s(0)/m_{ab}$ ratio peaks near optimal doping.

The model captures the doping dependence of various cuprate characteristics.

Abstract

Using a doping-determined multiband model spectrum of a "typical'' cuprate the effective mass of the paired carriers is calculated on the whole doping scale. Large $m_{ab}$ values quench rapidly with leaving the very underdoped region. Further slower diminishing of $m_{ab}$ reproduces the trend towards restoring the Fermi-liquid behaviour in cuprates with progressive doping. The interband superconducting condensate density ($n_s$) shows similar behaviour to the transition temperature and superconducting gaps. The $n_s(0)/m_{ab}$ ratio has an expressed maximum close to optimal doping as also the thermodynamic critical field. All the overlapping band components are intersected by the chemical potential at this. The pairing strength and the phase coherence develop simultaneously. In spite of its simplicity, the model describes the behaviour of various cuprate characteristics on the doping scale.