Sympathetic EIT laser cooling of motional modes in an ion chain

TL;DR

This paper demonstrates the use of electromagnetically induced transparency (EIT) laser cooling to efficiently cool motional modes in ion chains, achieving faster cooling times and lower laser intensities compared to traditional methods.

Contribution

It introduces EIT laser cooling as a sympathetic cooling technique for ion chains, significantly reducing cooling duration and laser power needed.

Findings

Approximately tenfold reduction in cooling time.

Significant decrease in laser intensity requirements.

Effective cooling of multiple ion chain configurations.

Abstract

We use electromagnetically induced transparency (EIT) laser cooling to cool motional modes of a linear ion chain. As a demonstration, we apply EIT cooling on $^{24}Mg^+$ ions to cool the axial modes of a $^9Be^+$ - $^{24}Mg^+$ ion pair and a $^9Be^+$ - $^{24}Mg^+$ - $^{24}Mg^+$ - $^9Be^+$ ion chain, thereby sympathetically cooling the $^{9}$Be$^{+}$ ions. Compared to previous implementations of conventional Raman sideband cooling, we achieve approximately an order-of-magnitude reduction in the duration required to cool the modes to near the ground state and significant reduction in required laser intensity.