Production of quantum degenerate strontium gases: Larger, better, faster, colder

TL;DR

This paper presents an improved method for producing larger, faster, and colder quantum degenerate gases of strontium, achieving record atom numbers, shorter cycle times, and deeper degeneracy, enabling advanced quantum experiments.

Contribution

The authors develop a new scheme that significantly enhances atom numbers, reduces cycle times, and refines the creation of various strontium quantum gases compared to prior methods.

Findings

Created 84-Sr BEC with over 10^7 atoms, a 30-fold increase.

Achieved 86-Sr BEC with 2.5x10^4 atoms, five times larger.

Generated deeply-degenerate 87-Sr Fermi gases with T/T_F as low as 0.10.

Abstract

We report on an improved scheme to generate Bose-Einstein condensates (BECs) and degenerate Fermi gases of strontium. This scheme allows us to create quantum gases with higher atom number, a shorter time of the experimental cycle, or deeper quantum degeneracy than before. We create a BEC of 84-Sr exceeding 10^7 atoms, which is a 30-fold improvement over previously reported experiments. We increase the atom number of 86-Sr BECs to 2.5x10^4 (a fivefold improvement), and refine the generation of attractively interacting 88-Sr BECs. We present a scheme to generate 84-Sr BECs with a cycle time of 2s, which, to the best of our knowledge, is the shortest cycle time of BEC experiments ever reported. We create deeply-degenerate 87-Sr Fermi gases with T/T_F as low as 0.10(1), where the number of populated nuclear spin states can be set to any value between one and ten. Furthermore, we report on a total of five different double-degenerate Bose-Bose and Bose-Fermi mixtures. These studies prepare an excellent starting point for applications of strontium quantum gases anticipated in the near future.