12 noon - 1pm
Thursday 10 October 2019

Seminar on topics in Quantum Biology

The role of noise in quantum decoherence in cellular systems
Lester Buxton
“Quantum mechanics has been applied to many areas of physics ranging from semiconductors, to computing, to cryptography. In  recent  years  the  study  of  quantum  biology  has  gained  momentum, highlighting the fundamental problem of explaining how biological systems may remain coherent in warm and wet cellular environments.  Making use of the Caldeira-Leggett model for open quantum systems, where the quantum system of interest is linearly coupled to a bath of harmonics oscillators, we study the effect of environmental noise on quantum decoherence. Adapting the Caldeira-Leggett model for this noisy system requires first the introduction of the Caldirola-Kanai Hamiltonian into the influence functional, in order to mimic environmental induced damping terms in the oscillators' equations of motion. This will be followed by including appropriate noise terms in the CK Hamiltonian. The general aim of this project is to see if this model can extend decoherence times of quantum systems.”

The effect of spectral density on decoherence dynamics of open quantum systems
Sapphire Lally
“The Caldeira-Leggett model is a successful way of describing the reduced dynamics of a multi-level quantum system in constant interaction with a reservoir of harmonic oscillators. In open quantum systems, the spectral density describes the distribution of reservoir frequency modes. The Caldeira-Leggett model assumes a spectral density which is Ohmic and Markovian. Initial experimental results suggest that a reservoir of harmonic oscillators has a strongly sub-Ohmic, non-Markovian spectral density. Here, the Caldeira-Leggett model is extended to an Ohmic non-Markovian spectral density, with the prospect of generalising to non-Ohmic spectral densities. This extended model should be applicable to a wide range of systems and may predict increased decoherence times of the quantum system.”


University of Surrey
back to all events

This event has passed

Visitor information

Find out how to get to the University, make your way around campus and see what you can do when you get here.