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Driven Radical Motion Enhances Cryptochrome Magnetoreception: Toward Live Quantum Sensing.

ABSTRACT: The mechanism underlying magnetoreception has long eluded explanation. A popular hypothesis attributes this sense to the quantum coherent spin dynamics and spin-selective recombination reactions of radical pairs in the protein cryptochrome. However, concerns about the validity of the hypothesis have been raised because unavoidable inter-radical interactions, such as the strong electron-electron dipolar coupling, appear to suppress its sensitivity. We demonstrate that sensitivity can be restored by driving the spin system through a modulation of the inter-radical distance. It is shown that this dynamical process markedly enhances geomagnetic field sensitivity in strongly coupled radical pairs via Landau-Zener-Stückelberg-Majorana transitions between singlet and triplet states. These findings suggest that a "live" harmonically driven magnetoreceptor can be more sensitive than its "dead" static counterpart.

SUBMITTER: Smith LD

PROVIDER: S-EPMC9677492 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Driven Radical Motion Enhances Cryptochrome Magnetoreception: Toward Live Quantum Sensing.

Smith Luke D LD Chowdhury Farhan T FT Peasgood Iona I Dawkins Nahnsu N Kattnig Daniel R DR

The journal of physical chemistry letters 20221104 45

The mechanism underlying magnetoreception has long eluded explanation. A popular hypothesis attributes this sense to the quantum coherent spin dynamics and spin-selective recombination reactions of radical pairs in the protein cryptochrome. However, concerns about the validity of the hypothesis have been raised because unavoidable inter-radical interactions, such as the strong electron-electron dipolar coupling, appear to suppress its sensitivity. We demonstrate that sensitivity can be restored ...[more]

PMID: 36332112

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