# Quantum entropic self-localization with ultracold fermions

## TL;DR

This paper investigates a driven fermionic lattice system with spin-orbit coupling, revealing entropic self-localization and constrained dynamics leading to quantum scars and localization phenomena.

## Contribution

It introduces an effective density-dependent tunneling model in a driven fermionic system, uncovering entropic self-localization and constrained dynamics at strong coupling.

## Key findings

- Even numbers of atoms propagate ballistically.
- Odd numbers form localized bound states.
- Connections to many-body scars and Anderson impurity models.

## Abstract

We study a driven, spin-orbit coupled fermionic system in a lattice at the resonant regime where the drive frequency equals the Hubbard repulsion, for which non-trivial constrained dynamics emerge at fast timescales. An effective density-dependent tunneling model is derived, and examined in the sparse filling regime in 1D. The system exhibits entropic self-localization, where while even numbers of atoms propagate ballistically, odd numbers form localized bound states induced by an effective attraction from a higher configurational entropy. These phenomena occur in the strong coupling limit where interactions only impose a constraint with no explicit Hamiltonian term. We show how the constrained dynamics lead to quantum few-body scars and map to an Anderson impurity model with an additional intriguing feature of non-reciprocal scattering. Connections to many-body scars and localization are also discussed.