Spatial inhomogeneity and chiral symmetry of the lattice incommensurate supermodulation in high temperature superconductor Bi2Sr2CaCu2O8+y

TL;DR

This study visualizes the spatial heterogeneity and chiral symmetry of incommensurate supermodulation in Bi2Sr2CaCu2O8+y, revealing large lattice fluctuations, chiral patterns, and intrinsic disorder at microscale.

Contribution

It provides a detailed real and reciprocal space mapping of lattice inhomogeneity and chiral symmetry in a high-temperature superconductor, highlighting intrinsic lattice disorder.

Findings

50% amplitude variation in supermodulation

Lattice exhibits left-handed chiral striped pattern

Correlation length of 50 μm with a compressed exponential decay

Abstract

Using scanning micro X-ray diffraction we report a mixed real and reciprocal space visualization of the spatial heterogeneity of the lattice incommensurate supermodulation in single crystal of Bi2Sr2CaCu2O8+y with Tc=84 K. The mapping shows an amplitude distribution of the supermodulation with large lattice fluctuations at microscale with about 50% amplitude variation. The angular distribution of the supermodulation amplitude in the a-b plane shows a lattice chiral symmetry, forming a left-handed oriented striped pattern. The spatial correlation of the supermodulation is well described by a compressed exponential with an exponent of 1.5 and a correlation length of about 50 {\mu}m, showing the intrinsic lattice disorder in high temperature superconductors.