# Improved magneto-optical trapping of Ca

## TL;DR

This paper improves calcium magneto-optical traps by exploring and experimentally validating alternative repumping schemes, significantly increasing trap lifetime, atom number, and density, approaching fundamental limits.

## Contribution

It identifies limiting factors in Ca MOTs and demonstrates new repumping schemes that substantially enhance trap performance.

## Key findings

- Trap lifetime increased up to ~5 seconds.
- Atom number and density improved by up to ~20x and ~6x.
- One repumping transition at 453 nm approaches the fundamental limit.

## Abstract

We investigate the limiting factors in the standard implementation of the Ca magneto-optical trap. We find that intercombination transitions from the 4s5p 1P1 state used to repump electronic population from the 3d4s 1D2 state severely reduce the trap lifetime. We explore seven alternative repumping schemes theoretically and investigate five of them experimentally. We find all five of these schemes yield a significant increase in trap lifetime and consequently improve the number of atoms and peak atom density by as much as ~20x and ~6x, respectively. One of these transitions, at 453 nm, is shown to approach the fundamental limit for a Ca magneto-optical trap with repumping only from the 3d4s 1D2 state, yielding a trap lifetime of ~5 s.