Quantum Technologies for Laser Interferometry

At our gravitational-wave and fundamental physics laboratories in Cardiff we are designing and building "QUEST", our bespoke, high precision co-located laser interferometers, which harness the precision technology and techniques that have been developed for gravitational wave detectors. Our goal is to further develop precision interferometry as a tool to answer pressing questions in fundamental physics. QUEST enables us to probe the nature of space-time and dark matter, look for signatures of primordial black holes, and inform the design of future upgrades to the worldwide network of gravitational wave detectors. The student will work on the commissioning (bringing into proper operation) our current initial version of the QUEST experiment. This includes commissioning of a new 'balanced homodyne' readout technique, to gain maximum benefit from quantum enhancement techniques such as squeezed light application in our experiment. In parallel, he will work on the design and implementation of techniques required for our future single photon readout technique, in particular the design, building and commissioning of triangular filter cavities that will be optimised for separating signal photons from non-signal photons. These filter cavities will enable single photon readout techniques for QUEST and other experiments with the goal of improving the sensitivity as compared to the current standard readout technique of homodyne or heterodyne interferometry.