Digital controlled analog servo with auto-lock for atomic, molecular, and optical experiments.

Area of Science:

• Atomic, Molecular, and Optical Physics
• Laser Physics
• Control Systems Engineering

Background:

• High-performance servo systems are essential for Pound-Drever-Hall (PDH) locking in ultra-stable lasers.
• Cold atom experiments require advanced timing control for enhanced functionality and flexibility.

Purpose of the Study:

• To develop a digital control high-performance analog servo system based on Field Programmable Gate Arrays (FPGAs).
• To integrate low-noise, high-bandwidth analog servo characteristics with FPGA capabilities for improved laser stabilization and experimental timing.

Main Methods:

• Implementation of a digital control servo system utilizing FPGAs.
• Characterization of the servo system's performance, including input noise levels (4.9 μV).
• Development of FPGA-based automatic locking and dynamic hold functionalities.

Main Results:

• The developed FPGA servo system achieves low input noise (4.9 μV) and high bandwidth.
• FPGA-implemented automatic locking ensures sustained PDH lock in unattended setups.
• Dynamic hold functionality enables real-time synchronization with atomic experiment timing.

Conclusions:

• The FPGA-based digital control analog servo system enhances PDH locking for ultra-stable lasers.
• The system provides crucial flexibility and functionality for cold atom experiment timing.
• A method to mitigate FPGA digital noise by disabling the clock was analyzed and proposed.