Dressed-atom multiphoton analysis of anomalous electromagnetically induced absorption

TL;DR

This paper introduces dressed-atom multiphoton spectroscopy (DAMS), a method for interpreting complex probe spectra in driven atomic systems, revealing that anomalous electromagnetically induced absorption (EIA) results from quantum interference between two-photon transitions.

Contribution

The paper presents DAMS as a novel approach to analyze probe spectra, providing a clear interpretation of anomalous EIA phenomena not explained by previous models.

Findings

Anomalous EIA arises from quantum interference between two-photon transitions.

DAMS effectively explains the dependence of EIA on coupling field strength.

The method clarifies the role of angular momentum configurations in EIA.

Abstract

A method to interpret probe spectra of driven degenerate atomic systems is discussed. The dressed-atom multiphoton spectroscopy (DAMS) is based on a dressing of the atomic system with the strong coupling field, followed by a perturbative treatment of the probe field interaction. As example, we apply the DAMS to provide a clear interpretation for anomalous electromagnetically induced absorption (EIA), which cannot be explained by spontaneous transfer of coherence. We show that anomalous EIA arises from quantum interference between competing two-photon transitions, and explain the different dependences on the coupling field strength observed for various angular momentum setups.