Rate My Professor Michael Cotterell

Michael Cotterell is an Associate Professor in Physical Chemistry in the Department of Chemistry at the University of Oxford, holding a joint appointment as a Tutorial Fellow and Governing Body Fellow at Corpus Christi College since September 2023. He completed an MSci in Chemical Physics at the University of Bristol in 2012 and a PhD there in 2016, supervised by Professors Jonathan Reid and Andrew Orr-Ewing FRS, developing Bessel laser beam optical traps integrated with cavity ring-down spectrometers to study evaporation and hygroscopic water uptake effects on single aerosol particles' optical properties. Following his doctorate, Cotterell undertook postdoctoral research at the University of Exeter from 2016 to 2019, collaborating with the Met Office on laser-based spectroscopy instruments for in-situ aerosol observations during atmospheric research aircraft campaigns; he received the Analytical Chemistry Trust Fund Tom West award during this period. In 2019, he secured a NERC Independent Research Fellowship at the University of Bristol, building his research group and obtaining principal investigator grants from EPSRC, NERC, and the Royal Society.

Cotterell's research employs advanced laser-based spectroscopic techniques, including Cavity Ring-Down Spectroscopy and Photo-Acoustic Spectroscopy, to probe the optical, physical, and chemical properties of aerosol particles ranging from 10 nm to 100 µm in diameter. His work addresses atmospheric aerosols' climate forcing, photobleaching kinetics, reaction acceleration in microdroplets, volatile species' interfacial dynamics, and morphological impacts on dried particles' densities and structures. He develops methods for single levitated particles using optical traps and electrodynamic balances, as well as ensemble measurements with size selection, supporting collaborations with the Met Office for airborne instrumentation. Key publications include 'The CLoud–Aerosol–Radiation interaction and forcing: Year 2017 (CLARIFY-2017) measurement campaign' (Atmospheric Chemistry and Physics, 2021), 'A Complete Parameterization of the Relative Humidity and Wavelength Dependence of the Refractive Index of Hygroscopic Inorganic Aerosol Particles' (Atmospheric Chemistry and Physics, 2017), 'Measurements of the evaporation and hygroscopic response of single fine-mode aerosol particles using a Bessel beam optical trap' (Physical Chemistry Chemical Physics, 2014), 'Accurate Measurement of the Optical Properties of Single Aerosol Particles Using Cavity Ring-Down Spectroscopy' (Journal of Physical Chemistry A, 2022), and 'Photoacoustic Studies of Energy Transfer from Ozone Photoproducts to Bath Gases following Chappuis Band Photoexcitation' (Physical Chemistry Chemical Physics, 2021). His contributions enhance quantification of aerosol light extinction, absorption, and scattering, informing climate models and environmental policy.