# Photoinduced polarization enhancement in biased bilayer graphene in the Landau level regime

## TL;DR

This study explores how monochromatic laser irradiation influences pseudospin polarization in bilayer graphene under Landau level quantization, revealing that higher Landau levels significantly enhance photoinduced polarization effects.

## Contribution

It demonstrates that higher Landau level transitions are crucial for enhancing photoinduced polarization in irradiated bilayer graphene, a novel insight into its charge dynamics.

## Key findings

- Photoinduced bandgaps cause oscillating pseudospin polarization responses.
- Higher Landau levels contribute significantly to polarization enhancement.
- Laser irradiation can control pseudospin polarization in bilayer graphene.

## Abstract

We investigate the charge carrier dynamics in bilayer graphene subject to monochromatic laser irradiation within the Landau level quantization regime. Even though the radiation field does not lift the energy degeneracy of the lowest Landau levels (LLs), it nevertheless has a strong effect on the photoinduced pseudospin polarization response for higher LLs ($n\ge2$). Our results show that the photoinduced bandgaps lead to a finite response of the averaged pseudospin polarization with nontrivial oscillating behavior. It is shown that the contribution from these higher LL transitions turns out to be crucial to achieve an enhanced photoinduced polarization in radiated bilayer graphene. The experimental feasibility of our findings is also discussed.