# Investigation of robust population transfer using quadratically chirped laser interacting with two-level system

## TL;DR

This paper introduces a fast, robust quantum state transfer method using quadratically chirped lasers, demonstrating improved efficiency and control over traditional linear chirping through numerical simulations.

## Contribution

It presents a novel approach employing quadratically chirped lasers for population transfer, enhancing speed and robustness compared to existing methods.

## Key findings

- Complete population transfer achieved with proper parameter tuning
- Transition time significantly reduced compared to linear chirping
- Stimulates intermediate transitions during nonadiabatic passage

## Abstract

We have proposed and demonstrated a fast and robust method of population transfer between two quantum states using a quadratically chirped laser source. Incorporating the Jaynes-Cummings in a full quantum description of the interaction, and numerically solving the time-dependent Schr\"odinger equation, transition probabilities have been obtained and the condition of the adiabatic passage is investigated. In this scheme, a laser source has been swept quadratically in time for arbitrarily engineering the transition probabilities. The results show that complete and robust population transfer could be selectively achieved by appropriate adjusting of the laser chirping parameter, the center frequency and the coupling strength which the time of the complete transition could be drastically decreased compared to linearly traditional chirped laser. Furthermore, another feature of using the quadratically chirped laser is the stimulation of intermediate transitions under the nonadiabatic passage.

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Source: https://tomesphere.com/paper/1902.04267