An active seismic isolation platform for precision measurement experiments is described. Piezo actuators are used to suppress seismic noise with a feedback control bandwidth of 0.3 to 3 Hz. Suppression levels ranging from 21 to 36 dB of seismic noise within the frequency range of 0.5 to 1.3 Hz are demonstrated!

We demonstrate the ability to manipulate the optical spring (OS) effect by integrating an optical parametric amplifier (OPA) into an optical cavity

For the first time ever, we demonstrate the suppression of parametric instability in an 80-meter-long Fabry-Perot cavity through optical actuation in an electro-optical feedback loop!

Using the polarization–modulation approach and a scanning system, we mapped the birefringence of a float zone silicon test mass in the <100> crystal orientation to assess the suitability of such material for future gravitational wave detectors!