Ability of dual balanced homodyne readout to subtract opto‑mechanical coupling of scattered light noise

Ascertain whether the dual balanced homodyne detection scheme that reads orthogonal quadratures at the symmetric and antisymmetric ports of a Michelson interferometer can also subtract the effects of opto‑mechanical coupling associated with scattered light noise.

Background

Beyond phase and amplitude contamination, scattered light can induce opto‑mechanical effects, such as radiation‑pressure‑mediated motion of optics, which may couple into the displacement readout in a more complex manner.

The authors explicitly flag as an open question whether their dual balanced homodyne approach can mitigate not only the optical interference component of scattered light, but also the opto‑mechanically mediated component, which is critical for application in gravitational‑wave interferometers.

References

Further effort should also be directed towards addressing open questions, such as the limitation of the scheme through different types of laser noise, as well as if the readout will also be able to subtract the effect of opto-mechanical coupling of scattered light noise.

— Dual balanced readout for scattered light noise mitigation in Michelson interferometers (2409.04266 - Lohde et al., 6 Sep 2024) in Section 5 (Conclusions)