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arXiv · 1206.5946

Entanglement and Sources of Magnetic Anisotropy in Radical Pair-Based Avian Magnetoreceptors

Hannah J. Hogben·Till Biskup·P. J. Hore
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Abstract

One of the principal models of magnetic sensing in migratory birds rests on the quantum spin-dynamics of transient radical pairs created photochemically in ocular cryptochrome proteins. We consider here the role of electron spin entanglement and coherence in determining the sensitivity of a radical pair-based geomagnetic compass and the origins of the directional response. It emerges that the anisotropy of radical pairs formed from spin-polarized molecular triplets could form the basis of a more sensitive compass sensor than one founded on the conventional hyperfine-anisotropy model. This property offers new and more flexible opportunities for the design of biologically inspired magnetic compass sensors.

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Hannah J. Hogben, Till Biskup, P. J. Hore. 2012-06-26. Entanglement and Sources of Magnetic Anisotropy in Radical Pair-Based Avian Magnetoreceptors. https://doi.org/10.1103/physrevlett.109.220501

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