A simple, powerful diode laser system for atomic physics

TL;DR

This paper introduces a high-power, simple, and versatile diode laser system suitable for atomic physics applications, achieving high spectral purity, wide tuning range, and sufficient power for trapping large numbers of atoms.

Contribution

The authors present a novel, cost-effective diode laser design with high power, narrow linewidth, and wide tuning, simplifying atomic physics experiments compared to complex traditional setups.

Findings

Achieves >210 mW power with 100 ms linewidth of ~427 kHz.

Provides >99% mode purity and 10 GHz mode-hop-free tuning.

Capable of trapping 10^10 rubidium atoms in a magneto-optical trap.

Abstract

External-cavity diode lasers are ubiquitous in atomic physics and a wide variety of other scientific disciplines, due to their excellent affordability, coherence length and versatility. However, for higher power applications, the combination of seed lasers, injection-locking and amplifiers can rapidly become expensive and complex. Here we present a useful, high-power, single-diode laser design with specifications: $>210\,$mW, $100\,$ms-linewidth ($427 \pm 7$) kHz, $>99\%$ mode purity, $10\,$GHz mode-hop-free tuning range and $12\,$nm coarse tuning. Simple methods are outlined to determine the spectral purity and linewidth with minimal additional infrastructure. The laser has sufficient power to collect $10^{10}$ $^{87}$Rb atoms in a single-chamber vapour-loaded magneto-optical trap. With appropriate diodes and feedback, the system could be easily adapted to other atomic species and laser formats.