Observation of Electromagnetically Induced Transparency and Slow Light in the Dark State - Bright State Basis of CPT

TL;DR

This paper reports the observation and analysis of electromagnetically induced transparency and slow light phenomena in a three-level atomic system using a novel bright and dark state basis, both theoretically and experimentally.

Contribution

It introduces and investigates EIT in a bright state - dark state basis, expanding understanding of EIT phenomena in different atomic state configurations.

Findings

EIT observed in bright-dark state basis is similar to standard EIT.

Transmission window width is comparable to conventional EIT.

Reduced group velocity of light confirmed in this basis.

Abstract

Electromagnetically induced transparency (EIT) is observed in a three-level system composed of an excited state and two coherent superpositions of the two ground-state levels. This peculiar ground state basis is composed of the so-called bright and dark states of the same atomic system in a standard coherent population trapping configuration. The characteristics of EIT, namely, width of the transmission window and reduced group velocity of light, in this unusual basis, are theoretically and experimentally investigated and are shown to be essentially identical to those of standard EIT in the same system.