arXiv subjects

Sibilla Di Pace

Publications and source records attributed to Sibilla Di Pace.

3 recordsLinked to original sources

arXiv2020

Finite state machine controls for a source of optical squeezed vacuum

In this paper we present a software, developed in the distributed control system environment of the Virgo gravitational-wave detector, for the management of a highly automated optical bench. The bench is extensively used for the research and development of squeezed states of light generation in order to mitigate the quantum noise in the next generations of interferometric gravitational-wave detectors. The software is developed using Finite-State Machines, recently implemented as a new feature of damping-adv Software Development Kit. It has been studied for its ease of use and stability of operation and thus offers a high duty-cycle of operation. Much attention has been drawn to ensure the software scalability and integration with the existing Data AcQuisition and control infrastructure of the Virgo detector.

physics.ins-det↗

arXiv2019

Generation of very high-order high purity Gaussian modes via spatial light modulation

We experimentally demonstrate the conversion of a fundamental $\text{TEM}_{00}$ laser mode at 1064\,nm to higher order Hermite-Gaussian modes (HG) of arbitrary order via a commercially available liquid crystal Spatial Light Modulator (SLM). We particularly studied the $\text{HG}_{5,5}/\text{HG}_{10,10}/\text{HG}_{15,15}$ modes. A two-mirror plano-spherical cavity filters the higher-order modes spatially. We analyze the cleaned modes via a three-mirror diagnosis cavity and measure a mode purity of 96/93/78\% and a conversion efficiency of 6.6\%/3.7\%/1.7\% respectively. The generated high-purity Hermite-Gaussian modes can be employed for the mitigation of mirror thermal noise in optical cavities for both optical clocks and gravitational wave (GW) detectors. HG modes are then converted into high order LG modes which can be of particular interest in cold atom physics.

gr-qc↗

arXiv2018

Study of the coherent perturbation of a Michelson interferometer due to the return from a scattering surface

We describe a setup based on Michelson interferometry for coherent measurements of the backscattered light from a low roughness optical surface under test. Special data processing was developed for the extraction of the useful signal from the various stray contributions to the coherent signal. We achieve coherent detection of light scattered by a mirror down to -130 dB in optical power. We characterize the dependence of the backscattered light with spot position and incidence angle. Results of cross-polarization scattering coherent measurements and preliminary results of dust deposition experiment are presented here. This work represents the first step in the experimental evaluation of the coherent perturbation induced by the scattered light in space gravitational wave detector of the LISA mission.

astro-ph.IM↗