Dynamical Properties of Charged Stripes in La_{2-x}Sr_xCuO_4

TL;DR

This study provides direct evidence of quasi-one-dimensional charged stripe formations in La_{2-x}Sr_xCuO_4, revealing their orientation, temperature dependence, and relation to superconductivity through inelastic light-scattering spectra.

Contribution

It presents the first direct spectroscopic evidence of stripe orientation and their temperature-dependent behavior in LSCO, linking electron-lattice interactions to superconducting properties.

Findings

Stripe orientation varies with doping level.

Correlation length depends on electron-lattice interaction.

Temperature governs the spectral response, indicating quantum criticality.

Abstract

Inelastic light-scattering spectra of underdoped ${\rm La_{2-x}Sr_xCuO_4}$ (LSCO) single crystals are presented which provide direct evidence of the formation of quasi one-dimensional charged structures in the two-dimensional $\rm CuO_2$ planes. The ``stripes'' manifest themselves in a Drude-like peak at low energies and temperatures. The selection rules allow us to determine the orientation to be along the diagonals at $x=0.02$ and along the principal axes at $x=0.10$. The electron-lattice interaction determines the correlation length which turns out to be larger in compound classes with lower superconducting transition temperatures. Temperature is the only scale of the response at different doping levels demonstrating the importance of quantum critical behavior.