Superfrustration of charge degrees of freedom

TL;DR

This paper reviews recent findings on superfrustration, a phenomenon where supersymmetric lattice models of strongly interacting fermions exhibit extensive degeneracy of ground states due to frustration.

Contribution

It introduces the concept of superfrustration in supersymmetric lattice models and provides multiple examples across various 2D lattices.

Findings

Superfrustration leads to extensive ground state degeneracy.

Tuning kinetic and interaction terms induces supersymmetry and superfrustration.

Examples demonstrate superfrustration across different 2D lattice geometries.

Abstract

We review recent results, obtained with P. Fendley, on frustration of quantum charges in lattice models for itinerant fermions with strong repulsive interactions. A judicious tuning of kinetic and interaction terms leads to models possessing supersymmetry. In such models frustration takes the form of what we call superfrustration: an extensive degeneracy of supersymmetric ground states. We present a gallery of examples of superfrustration on a variety of 2D lattices.