Analysing Non-Markovian Open Quantum Systems to Understand the Role of the External Environment in Cryptochrome-Based Magnetoreception

Magnetoreception, the ability of some animals to sense the geomagnetic field, is a topic of considerable scientific intrigue. It is widely accepted that cryptochromes, a type of flavoprotein found in avian retinae, play a critical role in facilitating magnetoreception. Within cryptochromes, a radical pair is thought to be generated by photoactivation, the quantum coherent spin dynamics of which render the radical pair's subsequent recombination sensitive to magnetic fields. However, recent studies indicate that the response of isolated cryptochromes is too weak to account for effective magnetoreception, suggesting the need to consider interactions with the surrounding biological environment.
Conventionally, environmental interactions are expected to cause decoherence, reducing sensitivity to external fields. However, our preliminary studies suggest that, counterintuitively, it seems as though the environment itself reinforces spin coherences. Specifically, these interactions can be a source of non-Markovian behaviour, which, under certain conditions, can drive the spin dynamics and enhance the coherence and sensitivity of the system. This project aims to theoretically study the spin dynamics of radical systems subject to non-Markovian noise and driving . To this end, we will develop tools to treat the open-system spin dynamics of realistically complex radical pair systems under these conditions. We will then apply these approaches to radical pair processes beyond cryptochrome, such as lipid peroxidation.
Initial approaches will utilise hierarchical equations of motion (HEOM), with wave-function based extensions coming later. Non-Markovian effects have not been previously studied in radical spin dynamics, but preliminary analysis suggests that they may be key to understanding magnetoreception. This project will provide critical insights with potential applications in biomimetic quantum technology and a deeper understanding of quantum effects in biological systems