Digital laser frequency control and phase stabilization loops for a high precision space-borne metrology system

Abstract

We report on the design, implementation and characterization of fully digital control loops for laser frequency stabilization, differential phase-locking and performance optimization of the optical metrology system on-board the LISA Pathfinder space mission. The optical metrology system consists of a laser with modulator, four Mach-Zehnder interferometers, a phase-meter and a digital processing unit for data analysis. The digital loop design has the advantage of easy and flexible controller implementation and loop calibration, automated and flexible locking and resetting, and improved performance over analogue circuitry. Using the practical ability of our system to modulate the laser frequency allows us to accurately determine the open loop transfer function and other system properties. Various noise sources and their impact on system performance are investigated in detail.

10 pages, 7 figures; draft only, for edited version see journal link

References in corpus (4)

• Frequency Comparison of Two High-Accuracy Al+ Optical Clocks
• Sub-Hz line width diode lasers by stabilization to vibrationally and thermally compensated ULE Fabry-Perot cavities
• Measurement of the absolute wavefront curvature radius in a heterodyne interferometer
• Coupling characterization and noise studies of the Optical Metrology System on-board the LISA Pathfinder Mission

Cited by in corpus (4)

• Transient acceleration events in LISA Pathfinder data: properties and possible physical origin
• Thermo-elastic induced phase noise in the LISA Pathfinder spacecraft
• Common mode noise rejection properties of amplitude and phase noise in a heterodyne interferometer
• Fundamental Performance Determining Factors of the Ultrahigh-Precision Space-Borne Optical Metrology System for the LISA Pathfinder mission