We harness light to probe the chemical structure of materials from bacteria to whiskey using Raman spectroscopy. We also develop innovative methods to measure properties of the light itself, by scrambling it into grainy speckle patterns. 

Raman Spectroscopy

Laser light can excite molecules to emit Raman photons which contain important chemical fingerprints of the samples. Wavelength modulated Raman spectroscopy (WMRS) efficiently removes the auto-fluorescence from biological samples, such as cells or tissue, therefore hugely enhances the signal to noise level and its detection ability. We use this for analysis of chemicals ranging from bacteria to whiskey!

Speckle Metrology

When laser light hits a rough surface, the light is scattered in many directions and the resultant interference pattern has a grainy appearance which we call speckle. This speckle is often considered as a loss of any information contained in the laser light, as much research has been devoted to avoiding it. However, the speckle is actually rich in information about both the laser and the scatterer. We have used this phenomenon to perform highly accuarate measurements of laser parameters, such as attometre-resolved wavelength measurement and characterisation of the orbital angular momentum contained in the light beam.