Effects of static and dynamic higher-order optical modes in balanced homodyne readout for future gravitational waves detectors

Abstract

With the recent discovery of Gravitational waves, marking the start of the new field of GW astronomy, the push for building more sensitive laser-interferometric gravitational wave detectors (GWD) has never been stronger. Balanced homodyne detection (BHD) allows for a quantum noise limited readout of arbitrary light field quadratures, and has therefore been suggested as a vital building block for upgrades to Advanced LIGO and third generation observatories. In terms of the practical implementation of BHD, we develop a full framework for analyzing the static optical high order modes (HOMs) occurring in the BHD paths related to the misalignment or mode matching at the input and output ports of the laser interferometer. We find the effects of HOMs on the quantum noise limited sensitivity is independent of the actual interferometer configuration, e.g. Michelson and Sagnac interferometers are effected in the same way. We show that output misalignment only effects the high frequency part of the quantum noise limited sensitivity. However, at low frequencies, HOMs reduce the interferometer response and the radiation pressure noise by the same amount and hence the quantum noise limited sensitivity is not negatively effected. We show that the input misalignment to the interferometer produces the same effect as output misalignment and additionally decreases the power inside the interferometer. We also analyze dynamic HOM effects, such as beam jitter created by the suspended mirrors of the BHD. Our analyses can be directly applied to any BHD implementation in a future GWD. Moreover, we apply our analytical techniques to the example of the speed meter proof of concept experiment under construction in Glasgow. We find that for our experimental parameters, the performance of our seismic isolation system in the BHD paths is compatible with the design sensitivity of the experiment.

References in corpus (12)

• Observation of Gravitational Waves from a Binary Black Hole Merger
• Enhancing the sensitivity of the LIGO gravitational wave detector by using squeezed states of light
• Conversion of conventional gravitational-wave interferometers into QND interferometers by modifying their input and/or output optics
• First Long-Term Application of Squeezed States of Light in a Gravitational-Wave Observatory
• Quantum Measurement Theory in Gravitational-Wave Detectors
• Interferometer Techniques for Gravitational-Wave Detection
• Sagnac Interferometer as a Speed-Meter-Type, Quantum-Nondemolition Gravitational-Wave Detector
• DC-readout of a signal-recycled gravitational wave detector
• QND measurements for future gravitational-wave detectors
• Design of a speed meter interferometer proof-of-principle experiment
• Quantum noise of non-ideal Sagnac speed meter interferometer with asymmetries
• Local-Oscillator Noise Coupling in Balanced Homodyne Readout for Advanced Gravitational Wave Detectors

Cited by in corpus (7)

• Advanced quantum techniques for future gravitational-wave detectors
• Mitigating mode-matching loss in nonclassical laser interferometry
• Multi-spatial-mode effects in squeezed-light-enhanced interferometric gravitational wave detectors
• Feasibility study of beam-expanding telescopes in the interferometer arms for the Einstein Telescope
• Quantum Squeezing Schemes for Heterodyne Readout
• Quantum noise cancellation in asymmetric speed meters with balanced homodyne readout
• Quantum noise and vacuum fluctuations in balanced homodyne detections through ideal multi-mode detectors