# Suppression of multiphoton resonances in driven quantum systems via pulse shape optimization

## TL;DR

This paper presents a method to suppress multiphoton resonances in driven quantum systems by optimizing the spectral shape of the driving pulse using Floquet theory and differential evolution, leading to controlled quantum transitions.

## Contribution

It introduces a pulse shape optimization technique to control multiphoton processes in two-level quantum systems, a novel approach for resonance suppression.

## Key findings

- Suppression achieved through Fourier coefficient optimization.
- Coherent superposition of harmonics closes the dynamical gap.
- Method applicable to superconducting qubits and laser-irradiated graphene.

## Abstract

This Letter demonstrates control over multiphoton absorption processes in driven two-level systems, which include for example superconducting qubits or laser-irradiated graphene, through spectral shaping of the driving pulse. Starting from calculations based on Floquet theory, we use differential evolution, a general purpose optimization algorithm, to find the Fourier coefficients of the driving function that suppress a given multiphoton resonance in the strong field-regime. We show that the suppression of the transition probability is due to the coherent superposition of high-order Fourier harmonics which closes the dynamical gap between the Floquet states of the two-level system.