Application of RWA leads to false conclusions about the transition probability for the near or exact resonance

TL;DR

This paper demonstrates that using the rotating wave approximation (RWA) in quantum optics can lead to incorrect conclusions about transition probabilities near or at resonance, challenging its assumed validity.

Contribution

It provides the first analytical and numerical evidence that RWA may produce false results in transition probability calculations at resonance.

Findings

RWA can lead to false conclusions about transition probabilities.

The validity of RWA is challenged near or at resonance.

Analytical and numerical methods confirm the inaccuracies of RWA.

Abstract

Rotating wave approximation (RWA) plays a key rule in quantum optics to solve some Schr\"{o}dinger equation approximately. For example, it is well known that RWA has been used to calculate the transition probability. However, so far no one shows the validity of RWA. Recently Larson [J. Larson, Phys. Rev. Lett. 108, 033601 (2012)] gave the first example showing that the application of RWA in the Jaynes-Cummings model may lead to false conclusions. In this paper, we analytically and numerically show that the application of RWA leads to false conclusions about the transition probability for the near or exact resonance.