Vibronic coherence in light-harvesting systems

Mar04Wed

Vibronic coherence in light-harvesting systems

Wed, 04/03/2020 - 14:30 to 15:30

Location:

Speaker: 
Professor Alexandra Olaya-Castro
Affiliation: 
UCL
Synopsis: 

Quantum biology is one of the most exciting scientific fields of the 21rst century bridging two seemingly distant scientific areas, namely, quantum science and biology. While the origins of this, at times dissonant, dialog dates back to the beginning of quantum mechanics, access to recent experimental, technological and theoretical developments are changing the way we address the question of how quantum science can help investigating biology at the molecular scale. In particular, recent experimental and theoretical work are pointing out to the influence of non-trivial quantum phenomena affecting ultrafast energy transfer processes in photosynthesis. There is mounting evidence that vibronic coupling and the associated quantum mechanical exchange of energy between excitonic and vibrational degrees of freedom in photosynthetic complexes could be at the heart of the counterintuitive long-lived coherence beating probed by ultrafast spectroscopy of such systems. Within this hypothesis, intramolecular vibrations influence excited-state dynamics through the formation of joint quantum states of excitonic and vibrational degrees of freedom. The exact influence such vibronic coupling on excited state dynamics is however not fully understood. In this talk I will discuss implications of coherent vibronic coupling for understanding truly quantum effects during energy transfer, energy conversion and synchronisation processes in prototype light-harvesting systems as well as a quantum-optical proposal to text experimentally the quantum coherent nature of the vibronic interactions in such systems.

Biography: 

Professor Alexandra Olaya-Castro did her undergraduate and master studies in Bogotá, Colombia and immigrated to the UK in 2002. She earned a DPhil in Physics from the University of Oxford in 2005 and subsequently obtained a three-year Junior Research Fellowship at Trinity College, University of Oxford. In 2008 she moved to UCL with an EPSRC Career Acceleration Fellowship. She became a Lecturer in 2011, was promoted to Reader in 2015 and became Professor in 2018. Olaya-Castro’s research career has focussed on the role of quantum coherence in a variety of systems ranging from Bose-Einstein condensates of excitons through to excitation dynamics in biomolecules to the understanding of the quantum to classical transition. Her theoretical contributions to quantum effects in biomolecules made her the recipient of the 2016 Maxwell Medal and Prize by the Institute of Physics in London. Olaya-Castro is also the Vice-Dean for Equality, Diversity and Inclusion in the UCL Mathematical and Physical Science faculty, from where she aims to contribute to facilitating the cultural change that scientific environments need.

Institute: