Frequency Stability of Atomic Frequency Standards beyond Quantum Projection Noise

TL;DR

This paper demonstrates that atomic frequency standards can surpass quantum projection noise limits by employing squeezed light for detection, offering a practical approach to enhance frequency stability.

Contribution

It introduces a method of creating atomic entanglement in the detection region using squeezed light, improving frequency stability beyond quantum noise limits.

Findings

Frequency stability exceeds quantum noise limit using squeezed light.

Entanglement creation in detection region is more practical than in microwave region.

Technical noise removal enhances the advantage of squeezing.

Abstract

In this paper we describe that the optically pumped frequency standards can have frequency stability beyond the quantum noise limit by detecting the Ramsey resonance through the squeezed light. In this paper we report that instead of considering the interaction of entangled atoms in the microwave region, it will be more practical to create the entanglement of the atoms in the detection region using the squeezed light, which is also used for the detection of the Ramsey resonance. The advantage of squeezing can be derived when the technical noises have been removed.