Quantum Coherence Effects in Four-level Diamond Atomic System

TL;DR

This paper investigates quantum coherence phenomena in a symmetric four-level diamond atomic system driven by four optical fields, revealing effects like dark resonances and double electromagnetically induced transparency relevant for quantum phase gates.

Contribution

It introduces the study of quantum interference effects in a four-level diamond atomic system and demonstrates how symmetry breaking leads to novel phenomena like double EIT.

Findings

Double electromagnetically induced transparency observed

Single and double dark resonances identified

Potential application in quantum phase gate implementation

Abstract

A symmetric four-level closed-loop $\diamondsuit$ type (the diamond structure) atomic system driven by four coherent optical fields is investigated. The system shows rich quantum interference and coherence features. When symmetry of the system is broken, interesting phenomena such as single and double dark resonances appear. As a result, the double electromagnetically induced transparency effect is generated, which will facilitate the implementation of quantum phase gate operation.