Mott insulators with boundary zeros

Area of Science:

• Condensed Matter Physics
• Topological Matter
• Strongly Correlated Systems

Background:

• Topological classification of electronic band structures relies on symmetry properties of Bloch eigenstates.
• Topological field theory characterizes non-trivial phases driven by electron-electron interactions.
• The connection between non-interacting band topology and Mott phase physics remains largely unexplored.

Purpose of the Study:

• To investigate the relevance of underlying non-interacting band topology to the physics of Mott phases.
• To establish a topological characterization of Mott phases using Green's function zeros.
• To predict new phenomena arising from the interplay of band and Mott topology.

Main Methods:

• Analysis of the momentum structure of Green's function zeros, defining the 'Luttinger surface'.
• Relating the topological properties of the Luttinger surface to single-particle electronic dispersion.
• Theoretical prediction of phenomena in topological Mott insulators based on zero properties.

Main Results:

• The 'Luttinger surface' zeros provide a topological characterization of Mott phases, linked to band topology.
• A topological Mott insulator with an inverted bulk gap exhibits gapless boundary zeros ('topological antimatter').
• Contact between band and Mott topological insulators creates observable interfacial signatures of Green's function zeros.

Conclusions:

• The topological properties of Green's function zeros offer a new perspective on Mott insulator classification.
• Predicted 'topological antimatter' states can annihilate conventional edge states, leading to novel physics.
• Interfacial signatures provide a pathway to experimentally probe elusive Green's function zeros in topological materials.