Adiabatic Population Transfer Based on a Double Stimulated Raman Adiabatic Passage

Abstract

Stimulated Raman adiabatic passage (STIRAP) is an adiabatic population-transfer technique that uses two coherent laser pulses in counter-intuitive order, namely, pump and stoke, to achieve complete transfer between two quantum states. Here, we propose a double STIRAP scheme whereby the electronic levels of a four-level atom are coupled by three laser fields forming two pairs of stoke and pump pulses. We derive the optical Bloch equations through the master equation for studying the population dynamics. We show that manipulating the time between two STIRAP sequences provides the state transfer near unity. In particular, we show that there occurs a certain maximum transfer efficiency that can be achieved in the double STIRAP process.