1.6 GHz Frequency Scanning of a 482 nm Laser Stabilized using Electromagnetically Induced Transparency

TL;DR

This paper presents a method for continuously shifting the frequency of a stabilized laser by about 1.6 GHz using electromagnetically induced transparency in rubidium vapor, enabling precise frequency scanning for atomic physics experiments.

Contribution

The authors demonstrate a novel technique to achieve large, stable frequency shifts of a laser via phase modulation of a reference laser using EIT signals.

Findings

Achieved 1.6 GHz frequency shift of the target laser.

Utilized cascaded electromagnetically induced transparency in rubidium vapor.

Provided a simple, stable method for GHz-range laser frequency scanning.

Abstract

We propose a method to continuously frequency shift a target laser that is frequency stabilized by a reference laser, which is several hundreds of nanometers detuned. We demonstrate the technique using the 5S 1/2 to 5P 3/2 to 29D 5/2 Rydberg transition in 87Rb vapor and lock the 482 nm target laser to the 780 nm reference laser using the cascaded electromagnetically induced transparency signal. The stabilized frequency of the target laser can be shifted by about 1.6 GHz by phase modulating the reference laser using a waveguide-type electro-optical modulator. This simple method for stable frequency shifting can be used in atomic or molecular physics experiments that require a laser frequency scanning range on the order of several GHz.