# Robust band of critical states in T broken fermionic systems with lattice selective disorder

## TL;DR

This paper discovers a robust band of critical states in certain 2D fermionic lattice systems with uneven disorder, revealing new localization phenomena in the unitary class A with broken spin symmetry.

## Contribution

It introduces a novel disorder configuration leading to critical states in class A systems, contrasting with traditional localization results.

## Key findings

- Critical states form a band in systems with uneven disorder distribution.
- Robustness of critical states persists despite disorder, measurable in optical lattices.
- Critical states occur when the less disordered sublattice is connected and breaks time reversal symmetry.

## Abstract

We analyze the localization properties of two dimensional systems based on partite lattices with a basis. Contrary to standard results, we find that a band of critical states emerges for systems in the unitary class A preserving spin symmetry when disorder is unevenly distributed over the basis atoms. The critical metal arises when the less disordered sublattice is connected and has time reversal symmetry broken. The unexpected robustness to disorder presented here is an appealing result which can be measured in optical lattices.