Precision optomechanical sensing
Optical techniques offer exquisite precision in measurements of motion. This is most prominently illustrated by the recent successful detection of gravitational waves in kilometre scale interferometer which required measurements with attometre resolution - a thousandth of the width of a proton. However, optical measurements have far broader applications, from observation of nanoscale motion in biology to clocks and inertial sensors in mobile electronics. In our laboratory we seek to apply the precision technologies developed for gravitational wave detection and other major scientific endeavors, into these applications. We focus on silicon chip-integrated sensors and apply them in areas ranging from precision room temperature magnetometry, to accelerometry and acoustic sensing. Recent results include:
-  Demonstration that radiation pressure forces can be used to amplify signals encoded on mechanical motion, and ultimately even exceed the standard quantum limit induced by the Heisenberg uncertainty principle. Applied Physics Letters 100, 201101 (2012).
-  First demonstration that feedback can improve the sensitivity of mechanical sensors in the presence of parametric instability. Potentially important to overcome major issues in next generation gravitational wave detectors Physical Review A85, 061802(R) (2012).
-  Proposal and demonstration of cavity optomechanical magnetometry. Predicted to allow state-of-the-art sensitivity without the usual cryogenics, and therefore considerably expand the range of applications. Physical Review Letters 108, 120801 (2012).
-  Demonstration of orders of magnitude enhanced precision in cavity optomechanical magnetometry. Advanced Materials 26, 6348–6353 (2014). and highlighted in Nature | News & Views 547, 164-165 (2017).
-  Proof that feedback cannot be used to enhance the precision of linear sensors. Resolved a significant outstanding question in optomechanical sensing. Physical Review Letters 110, 184301 (2013).
-  Demonstration of injection locking of an electro-optomechanical device Optica 4, 10, 1196-1204 (2017).