Available student project - Dual torsion pendulum for quantum noise limited sensing

Research fields

Project details

With the recent detection of gravitational waves by LIGO, the quest to further improve the astrophysical range and the detector's sensitivity is in full swing. At the ANU Centre for Gravitational Physics we have installed various hardware in the current LIGO detectors. 

As part of the national ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav) we want to continue to be at the forefront of instrumentation development to enhance the sensitivity of current and future gravitational wave detectors around the world.

Interferometric sensing of the quantum limit is a challenging task. Optical interferometry, such as in LIGO, is used to readout the differential torsion motion of a dual torsion pendulum. With the optical readout, we aim to be limited by the quantum shotnoise and the quantum radiation pressure noise. The junction between these two quantum noise sources is called the standard quantum limit. To reach this limit a low noise mechanical system is required, in particular the system will need to have a  low thermal noise level.

Reducing the mechanical resonant frequency into the milli-Hertz regime, a large enough clearance between the thermal noise and the quantum radiation pressure nosie can be achieved. This project will prototype a torsion pendulum to obtain such a low mechanical resonant frequency.

The student will measure and characterise the mechanical system by comparing the data with the mechanical model. During the project, the student will develop skills in electronics, optics, mechanical design and control systems.

The Centre for Gravitational Physics, has 4 academics, 4 post-docs and 19 students, provides a vibrant research environment with research ranging from quantum opto-mechanics, classical optics, high power laser, fibre optics, fibre sensing.

Find out more by following the Further Information link below, or by visiting the Centre for Gravitational Physics website

Required background

mechanics, control theory, optics

Project suitability

This research project can be tailored to suit students of the following type(s)

Contact supervisor

Slagmolen, Bram profile

Other supervisor(s)

McClelland, David profile