Birefringent atomic vapor laser lock in a hollow cathode lamp

TL;DR

This paper introduces a new laser stabilization technique using birefringence in a hollow cathode lamp, offering a robust alternative to traditional methods for atomic transition locking.

Contribution

It presents a novel birefringence-based laser locking method in hollow cathode lamps, differing from the standard dichroic atomic vapor laser lock by using a transversal magnetic field.

Findings

Successfully stabilized laser frequency using the new method.

Achieved a strong error signal with maximum slope.

Applicable to various hollow cathode lamps and atomic species.

Abstract

We report a robust method of stabilizing a laser to the frequency of an atomic transition using a hollow cathode lamp. In contrast to the standard dichroic atomic vapor laser lock (DAVLL) method, which uses dichroism induced by a longitudinal magnetic field, we employ birefringence induced by a transversal magnetic field. We applied this method to the $(5s^2)\ {}^{1}S_{0} - (5s5p)\ {}^{1}P_{1}$ transition (461 nm) of Sr. Although the hollow cathode is made of ferromagnetic material, we successfully applied a magnetic field of sufficient strength to obtain an error signal with a theoretical maximum slope. This method may be applied to other hollow cathode lamps of different atomic species.