Laser frequency stabilization with the use of homodyne quadrature interferometers

Laser frequency stabilization is a crucial technique for precision metrology. We demonstrate laser frequency control using a compact, interferometric sensor, specially modified for sensitivity to laser frequency noise. This setup achieves a balance between compact size, ease of use, and affordability. We stabilize the laser frequency noise, of a low-cost solid-state laser, to 4.5 kHz Hz-1 at 1 Hz. The requirement for additional technology, and expense, is negated when identical, compact, interferometric sensors are deployed. The use of compact interferometric sensors is already a technology under investigation for integration into gravitational-wave observatories and out study enables wider applications by mitigating a fundamental noise source, inherent to their design.