Digital laser frequency and intensity stabilization based on the STEMlab platform (originally Red Pitaya).

Area of Science:

• Physics
• Optical Engineering
• Control Systems

Background:

• Laser systems require precise frequency and intensity stabilization for various scientific applications.
• Existing stabilization methods can be complex or costly.
• The STEMlab platform offers a flexible and accessible hardware base for developing custom control solutions.

Purpose of the Study:

• To develop and characterize digital controllers for laser frequency and intensity stabilization.
• To leverage the STEMlab platform for implementing these controllers.
• To provide open-source hardware designs for wider accessibility.

Main Methods:

• Development of analog hardware interfaces compatible with the STEMlab platform.
• Implementation of digital control algorithms for laser stabilization.
• Characterization of controller performance, including bandwidth and noise.
• Demonstration of frequency stabilization on a diode laser system.
• Implementation of intensity control using an acousto-optic modulator.

Main Results:

• The developed controllers are limited by the STEMlab system's bandwidth (1.25 MHz) and noise performance.
• Achieved a frequency-stabilized diode laser system with a linewidth of 52(1) kHz (FWHM).
• Demonstrated intensity control to the 1 × 10^-3 level with sub-microsecond rise and fall times.

Conclusions:

• The STEMlab-based digital controllers offer effective solutions for laser frequency and intensity stabilization.
• The open-source nature of the project promotes accessibility and further development.
• The controllers meet the demanding requirements for high-precision laser control in scientific research.