Modulation-free pump-probe spectroscopy of strontium atoms

TL;DR

This paper demonstrates modulation-free polarization spectroscopy and DAVLL techniques on strontium atoms, providing stable laser locking signals primarily driven by saturation effects, simplifying atomic spectroscopy methods.

Contribution

It introduces modulation-free polarization spectroscopy and DAVLL for strontium, avoiding frequency modulation and highlighting saturation effects as the main signal source.

Findings

Generated stable dispersion lineshapes suitable for laser locking.

Signal primarily due to saturation effects, not optical pumping.

Analyzed dependence of signals on intensity and magnetic field.

Abstract

We have performed polarization spectroscopy and sub-Doppler DAVLL on the (5s5s) 1^S_0 -> (5s5p) 1^P_1 transition of atomic strontium. Both techniques generated a dispersion-type lineshape suitable for laser stabilization, without the need for frequency modulation. In both cases the signal is generated primarily by saturation effects, rather than optical pumping. The dependence of the amplitude and gradient on intensity and magnetic field were also investigated.