The discovery of magnetic protein provides a new understanding of a biocompass at the molecular level. However, the mechanism by which magnetic protein enables a biocompass is still under debate, mainly because of the absence of permanent magnetism in the magnetic protein at room temperature. Here, based on a widely accepted radical pair model of a biocompass, we propose a microscopic mechanism that allows the biocompass to operate without a finite magnetization of the magnetic protein in a biological environment. With the structure of the magnetic protein, we show that the magnetic fluctuation, rather than the permanent magnetism, of the magnetic protein can enable geomagnetic field sensing. An analysis of the quantum dynamics of our microscopic model reveals the necessary conditions for optimal sensitivity. Our work clarifies the mechanism by which magnetic protein enables a biocompass.

中文翻译：

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启用电磁噪声的生物罗盘。

磁性蛋白质的发现为分子罗盘提供了新的认识。然而，磁性蛋白质实现生物罗盘的机制仍在争论中，主要是因为室温下磁性蛋白质中不存在永久磁性。在此，根据广泛接受的生物指南针的自由基对模型，我们提出了一种微观机制，该机制可使生物指南针在生物环境中不对磁性蛋白质进行有限的磁化。通过磁性蛋白质的结构，我们表明磁性蛋白质的磁波动而不是永久磁性可以实现地磁场感测。对我们微观模型的量子动力学的分析揭示了最佳灵敏度的必要条件。