Microscopic nature of $4a_0\times4a_0$ plaquettes in stripe LDOS and $2a_0$ shift

TL;DR

This paper uses a quantum color string model to explain the microscopic origin of specific LDOS patterns in cuprates, linking them to spinon singlet pairs and identifying a particle-hole symmetry breaking shift, advancing understanding of high-$T_c$ superconductors.

Contribution

It introduces a wavefunction-based model that explains STM LDOS patterns and reveals a particle-hole symmetry breaking effect in stripe cuprates.

Findings

$4a_0\times4a_0$ plaquettes are related to spinon singlet pairs

Identification of a $2a_0$ shift due to particle-hole symmetry breaking

Confirmation of the shift in longer stripe samples

Abstract

Scanning tunneling microscopy (STM) serves as a powerful pictorial tool for visualizing the local density of states (LDOS) of an individual stripe, which strongly intertwines with superconductivity in the underdoped cuprates. The exotic LDOS map patterns thus appear as the key to uncovering the mystery of the underlying microscopic mechanisms. With the quantum color string model framework, we reveal that the microscopic origin of the ubiquitous $4a_0\times4a_0$ plaquettes is closely related to spinon singlet pairs. Moreover, by comparing our data with LDOS of cuprates, we identify an effect of particle-hole symmetry breaking (PHSB): a $2a_0$ shift, which is confirmed in a longer stripe ($L=18$).Our work offers a fresh wavefunction-based perspective for interpreting STM signals in experiments and may advance the microscopic comprehension of high-$T_c$ cuprates.