Engineering single topological π-conjugated polymers and interpolating topological solitons by end-group...

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Technology

Background:

• Topological solitons act as domain walls between distinct topological phases.
• Experimental realization of topological solitons is challenging.
• Hybrid properties of solitons offer opportunities for quantum technologies.

Purpose of the Study:

• To demonstrate on-surface engineering of topological structures.
• To introduce topological solitons in π-conjugated pentacene polymers.
• To explore applications in quantum devices.

Main Methods:

• On-surface synthesis of cumulene-bridged pentacene oligomers and polymers on Au(111).
• End-group modification to create domain walls between topological phases.
• Characterization using scanning tunneling microscopy, non-contact atomic force microscopy, and tip-enhanced Raman spectroscopy.
• Theoretical validation through density functional theory and tight-binding calculations.

Main Results:

• Fabrication of pentacene polymers with length-independent properties.
• Realization of topological solitons as domain walls via end-group modification.
• Experimental and theoretical confirmation of solitonic zero-energy peaks, band reversal, and region-dependent vibrational modes.

Conclusions:

• Topological solitons were successfully realized as domain walls in engineered pentacene polymers.
• This provides a versatile platform for fundamental research in topological matter.
• Demonstrates potential applications of π-conjugated polymers in quantum devices.