论文标题
由自旋热力学控制的磁铁元素晶体的非线性高频磁反应
Nonlinear high-frequency magnetic response of magnetoferritin metacrystals governed by spin thermodynamics
论文作者
论文摘要
理论是关于由磁铁蛋白大分子组成的元晶体的时间依赖性磁化的。可以使用生化组装技术人为地创建这种封装在蛋白质壳中的超级磁性纳米颗粒，包括多达数百万的超顺磁性纳米颗粒。它们也已被证明自然存在于鸟类内耳的敏感细胞中，这表明它们可能参与检测地磁场以进行迁移动物的方向和导航。磁铁蛋白元晶体的磁系统的动力学，包括大量由远距离偶极力耦合的磁矩，非常复杂。为了找到元晶体对高频磁场的响应，我们使用了从固体的核自旋系统理论中借用的热力学方法。所得理论产生了由任意强度的振荡磁场引起的时间依赖性超级蛋白温度和磁化。高频反应对静态磁场的预测依赖性可用于生物组织中磁铁蛋白元晶体的实验检测和表征。
A theory is developed of the time-dependent magnetization of the metacrystal composed of magnetoferritin macromolecules. Such superstructures, comprising up to several millions of superparamagnetic nanoparticles encapsulated in protein shells, can be created artificially using biochemical assembling technologies. They have been also shown to occur naturally in sensitive cells of the inner ear of birds, which suggests their possible involvement in the detection of the geomagnetic field for orientation and navigation of migratory animals. The dynamics of the magnetic system of the magnetoferritin metacrystal, comprising a very large number of magnetic moments coupled by long-range dipole forces, is exceedingly complex. In order to find the response of the metacrystal to high-frequency magnetic fields, we used a thermodynamic approach borrowed from the theory of nuclear spin systems of solids. The resulted theory yields the time-dependent superspin temperature and magnetization induced by oscillating magnetic fields of arbitrary strength. The predicted dependence of the high-frequency response on the static magnetic field can be used for experimental detection and characterization of magnetoferritin metacrystals in biological tissues.
