# Strong frequency dependence of transport in the driven Fano-Anderson model

## TL;DR

This paper investigates how periodic driving affects transport in a disordered Fano-Anderson model, revealing frequency-dependent localization effects and the emergence of dark Floquet states that can nearly freeze transport.

## Contribution

It uncovers the frequency-dependent transport behavior and identifies dark Floquet states as a mechanism for localization in the driven Fano-Anderson model.

## Key findings

- Localization is enhanced at high frequencies due to reduced effective coupling.
- Dark Floquet states can nearly freeze transport at specific frequencies.
- Critical frequency $$ marks an abrupt increase in transport, linked to one-photon resonances.

## Abstract

We study a periodically driven central site coupled to a disordered environment. In comparison to the static model, transport features are either enhanced or reduced, depending on the frequency of the drive. We demonstrate this by analyzing the statistics of quasienergies and the logarithmic entanglement growth between bipartitions, which show similar features: For frequencies larger than disorder strength, localization is enhanced due to a reduced effective coupling to the central site. Remarkably, localization can even be increased up to almost perfect freezing at particular frequencies, at which the central site decouples due to the emergence of `dark Floquet states'. This high-frequency domain of our model is bounded by a critical frequency $\omega_c$, where transport increases abruptly. We demonstrate that $\omega_c$ is determined by one-photon resonances, which connect states across the mobility edge. This sensitive frequency dependence allows us to fine tune transport properties of the driven central site model, by unprecented precision.