Inversion-free, noiseless Raman echoes

TL;DR

This paper introduces an inversion-free, noiseless Raman echo technique using double optical Raman rephasing, enabling quantum memory applications without the noise issues caused by population inversion.

Contribution

It demonstrates a novel inversion-free Raman echo method with frozen propagation vector, reducing quantum noise and improving quantum interface potential.

Findings

Inversion-free Raman echoes are achieved with double optical Raman rephasing.

The method suppresses quantum noise associated with population inversion.

Potential for noiseless quantum memory applications.

Abstract

Using double optical Raman rephasing, an inversion-free resonant Raman echo is studied in an inhomogeneously broadened spin ensemble of a solid medium, where the Raman optical field-excited spin coherence has a frozen propagation vector. Unlike photon echoes whose quantum memory application is strictly limited due to \pi rephasing pulse-induced population inversion causing quantum noises, the optical Raman field-excited spin echo is inherently silent owing to the frozen propagation vector. Thus, the doubly rephased Raman echo can be directly applied for quantum interface in a population inversion-free environment.