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

Abstract

We have proposed and demonstrated a fast and robust method of population transfer between two quantum states using a quadratically chirped laser source. Numerically solving the time-dependent Schrödinger equation, transition probabilities have been obtained and the condition of the adiabatic passage is investigated. In this scheme, the wavelength of a laser source is quadratically swept in time to arbitrarily engineer the transition probabilities. The results show that complete and robust population transfer could be achieved by appropriate adjusting of the system parameters including the laser chirping parameter, the center frequency, and the coupling strength. Using this method, the time of the complete transition could be drastically decreased compared to the incorporation of the traditional linearly chirped laser.