Stripe-like nanoscale structural phase separation in superconducting BaPb(1-x)Bi(x)O3.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Solid-State Chemistry

Background:

• Barium lead bismuthate (BaPb(1-x)Bi(x)O3) exhibits a complex phase diagram.
• Superconductivity and charge density wave phases coexist in this material.

Purpose of the Study:

• To investigate the structural basis of superconductivity in BaPb(1-x)Bi(x)O3.
• To understand the relationship between structural phase separation and the superconducting dome.

Main Methods:

• High-resolution transmission electron microscopy (HRTEM).
• Analysis of nanoscale structural phase separation and length scales.

Main Results:

• Structural dimorphism in superconducting BaPb(1-x)Bi(x)O3 occurs as partially disordered nanoscale stripes.
• The superconducting coherence length was compared with the width of these stripes.
• Maximum critical temperature (Tc) correlates with the superconducting coherence length matching the stripe width.

Conclusions:

• The morphology of nanoscale structural phase separation is crucial for superconductivity in BaPb(1-x)Bi(x)O3.
• A direct link exists between structural phase separation and the superconducting dome's shape.