Knight shift vs hole concentration in Hg1201 and Hg1212

TL;DR

This study investigates how the 63Cu Knight shift varies with hole concentration in single-layer and double-layer Hg-based cuprate superconductors, revealing different behaviors and providing methods to estimate hole doping levels.

Contribution

It introduces a comparative analysis of Knight shifts in single- and double-layer cuprates and proposes two relations to estimate hole concentrations in non-equivalent CuO2 planes.

Findings

Knight shift behavior differs between single- and double-layer cuprates.

Two relations are proposed to estimate hole doping levels.

The results help understand the electronic properties of high-Tc cuprates.

Abstract

We studied the hole concentration dependences of 63Cu Knight shifts in single-CuO2-layer high-Tc cuprate superconductors HgBa2CuO4+d and double-layer HgBa2CaCu2O6+d. We found that the spin Knight shift at room temperature as a function of the hole concentration in the single-layer superconductor is different from that in the double-layer superconductor. Two type relations between the spin Knight shift and the hole doping level serve to estimate the individual hole concentrations of the non-equivalent CuO2 planes in a unit cell.