The Linewidth of Ramsey Laser with Bad Cavity

TL;DR

This paper introduces a Ramsey laser with a bad cavity that achieves a linewidth over two orders of magnitude narrower than natural atomic linewidth, enabling highly precise spectroscopy for advanced optical clocks and interferometers.

Contribution

It presents a novel laser scheme combining Ramsey separated-field technique with a bad cavity to significantly narrow linewidth beyond existing methods.

Findings

Linewidth is over two orders of magnitude narrower than atomic natural linewidth.

Cavity-related noise is minimized, reducing cavity-pulling effects.

Potential applications in next-generation optical clocks and atom interferometers.

Abstract

We investigate a new laser scheme by using Ramsey separated-field technique with bad cavity. By studying the linewidth of the stimulated-emission spectrum of this kind of laser inside the cavity, we find its linewidth is more than two orders of magnitude narrower than atomic natural linewidth, and it is far superior to that of conventional optical Ramsey method and any other available subnatural linewidth spectroscopy at present. Since any cavity related noise is reduced to cavity-pulling effect in bad cavity laser, this Ramsey laser provides the possibility of precision subnatural linewidth spectroscopy, which is critical for the next generation of optical clock and atom interferometers.