Systematic Raman study of optical phonons in $R$Ba${}_2$Cu${}_3$O${}_{6+\delta }$ ($R$ = Y, Dy, Gd, Sm, Nd): Antiferromagnetic coupling strength versus lattice parameters

Abstract

We present a systematic study of the interplay between lattice parameters and the energy of the optical phonons as well as the antiferromagnetic coupling strength, $J$, in the high-$T_{\text{c}}$ superconducting cuprate $R$Ba${}_2$Cu${}_3$O${}_{6+\delta }$ (\mbox{R-123}, $R=$ Y, Dy, Gd, Sm, Nd) with hole-doping $p$ ($0.00<p\lesssim 0.04$). The energy of the $B_{1g}$-mode at ${\nu }_{B1g}\approx 335$ cm${}^{-1}$ has been found to relate systematically to the inverse of the lattice parameter $a$. Our results confirm the temperature dependent phonon splitting for Nd-123 at low doping, which has been reported for optimally-doped Nd-123. Surprisingly, $J$ is independent of $a$ for the first four $R$ families, and a general consistency between $T_{\text{c}}^{\text{max}}$ and $J$, as suggested in a previous investigation, could not be confirmed.

5 pages, 4 figures

References in corpus (2)

• Inelastic Light Scattering From Correlated Electrons
• A magnetic analog of the isotope effect in cuprates

Cited by in corpus (1)

• Relevance of magnetism to cuprate superconductivity: Lanthanides versus charge-compensated cuprates