All-fiber, near-infrared, laser system at 780nm for atom cooling

TL;DR

This paper introduces a compact, fiber-based laser system at 780 nm designed for cold atom applications, featuring low noise and narrow linewidth, suitable for atom cooling and trapping.

Contribution

The authors develop and characterize a simple, economical all-fiber laser system at 780 nm using frequency doubling of 1560 nm lasers, optimized for quantum technology applications.

Findings

Amplitude noise of 3×10⁻⁴ at 1 s

Linewidths below 1 MHz

High SHG efficiency

Abstract

One of the prominent platforms for quantum technologies, cold atoms require reliable laser systems. We present the design, implementation, and characterization of a simple, compact, and economical laser system at 780 nm, entirely based on fiber components. Two semiconductor lasers at 1560 nm are amplified in a single Erbium-doped fiber amplifier and frequency-doubled in a periodically-poled lithium niobate crystal. We characterize the amplitude noise and the linewidths of the lasers, as well as the SHG efficiency. With a rms relative amplitude noise of 3$\times$10$^{-4}$ at 1 s and linewidths below 1 MHz, our system is suitable for cooling and trapping of Rb atoms.