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Updated: Sep 13, 2025

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

Published on: April 24, 2014

A multi-loop auto-locking system with fully digital electronics for ultra-stable laser.

Can Xia^1,2,3, DanYang Zhu^1,2,3, Yaodong Hu^1,2,3

¹Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China.

The Review of Scientific Instruments

|July 28, 2025

Summary

This summary is machine-generated.

A new digital auto-locking system enhances ultra-stable lasers (USLs) by integrating multiple control loops. This system achieves high frequency stability and rapid relocking, meeting demanding USL application requirements.

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Last Updated: Sep 13, 2025

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

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Published on: April 24, 2014

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Low-cost Custom Fabrication and Mode-locked Operation of an All-normal-dispersion Femtosecond Fiber Laser for Multiphoton Microscopy

Published on: November 22, 2019

Area of Science:

Laser Physics
Optical Engineering
Digital Electronics

Background:

Ultra-stable lasers (USLs) require complex multi-loop systems for high performance.
Existing systems often rely on analog electronics, limiting integration and flexibility.

Purpose of the Study:

To demonstrate a highly integrated, fully digital auto-locking system for USLs.
To improve the stability, reliability, and automation of USL frequency control.

Main Methods:

Implementation of a multi-loop auto-locking system using a field-programmable gate array (FPGA).
Integration of high-speed analog-to-digital and digital-to-analog converters for precise control.
Utilizing digital servo control for Pound-Drever-Hall (PDH), fiber noise cancellation (FNC), and light power stabilization (LPS) loops.

Main Results:

Achieved a fully digital open-loop bandwidth of 1.3 MHz for the fast feedback loop.
Demonstrated frequency instability of 1.5 × 10-15 (1s) in carrier-locking and 2.5 × 10-15 (1s) in offset-locking modes.
Reported noise suppression of 75 dB (FNC) and 40 dB (LPS) at 1 Hz.

Conclusions:

The digital auto-locking system successfully stabilizes laser frequency and demonstrates rapid relocking (<10s).
The system's digital nature contributes minimally to frequency instability (2.9 × 10-16 at 1s).
This flexible and reliable digital system meets the stringent requirements for advanced USL applications.