Patterned Hierarchies of Functional Materials

生命、意识、复制、磁性、液态结晶性和生物形态发生是我们所说的“涌现”性质。这些可以说是从模式的层次结构演变而来的。层次结构可以理解为一种分支树，它显示了不同部分是如何连接的。“树”作为树的功能仅取决于所有部分如何相互作用。这棵树，就像意识或生物形态发生一样，真的不能简化为原子和分子。涌现指的是部件聚集在一起产生某种模式的方式，这种模式与功能属性有关，比如传导光或磁性的能力。这些特性正是从零件的图案中显现出来的。在自然界中，硅藻（浮游植物）等微生物从水中吸收硅酸。硅酸是一种四面体4原子分子，硅藻用它来建造一个非常华丽的“玻璃屋”——一个被称为“壳”的保护壳。尽管玻璃本身在分子尺度上是无序的，但这种结构具有复杂的周期模式。硅藻负责人体每四次呼吸中的氧气，因此了解藻在光合作用中可能发挥的作用是有用的。我们怀疑，硅藻利用这种截叶作为一种复杂的光学装置来收集阳光，并将其输送到叶绿体中，以固定二氧化碳并制造氧气。在我们的研究中，我们使用理论模型并进行实验来展示硅藻如何在非常小的尺度上具有光子（光学）它们是纳米光子。我们展示了模式形成如何导致纳米光子行为。磁性也是电子有序排列的结果（铁磁性就是一个例子）。有一些不寻常的流体是由磁性纳米颗粒组成的铁磁流体，比如磁铁矿、Fe3O4。当这种液体的一个平坦的池子暴露在磁场中时，一个图案就会突然形成。这破坏了池的旋转对称性，我们称之为相变。打破对称性会产生模式。我们感兴趣的不仅是这些图案是如何形成的，还有如何将它们永久记录下来。我们已经发现了这样做的方法，我们在这个研究计划中描述了它。磁性材料的永久模式将使我们能够创造出新型的磁性材料，比如可以在磁场中移动的微型驱动器，来模仿微生物的纤毛或人类肺部的纤毛。这样的研究可以影响健康研究。最后，对模式结构的研究将告诉我们一些关于如何从模式中产生物质的新功能的新东西。正是由于这些原因，我们将我们的研究项目命名为“功能材料的模式层次”。

Life, consciousness, replication, magnetism, liquid crystallinity and biological morphogenesis are what we call "emergent" properties. These can be said to evolve from hierarchies of patterns. A hierarchy can be understood as a kind of branched tree that shows how its different parts are connected. The “tree” functions as a tree only by virtue of how all the parts interact. The tree, like consciousness or biological morphogenesis, is really not reducible to atoms and molecules. Emergence refers to the way that parts come together (assemble) to yield some sort of pattern that is connected to a functional property, like the ability to conduct light or magnetism. It is from the patterning of the parts that such properties emerge. In Nature, micro-organisms like diatoms (phytoplankton) take up silicic acid from water. Silicic acid is a tetrahedral 4-atom molecule that is used by the diatom to build a very ornate “glass house” - a protective shell called the frustule. The frustule has a complex periodic pattern, though the glass itself is disordered at the molecular scale. Diatoms are responsible for the oxygen in every 4th breath one takes, so it is useful to understand the role that the frustule might play in harvesting light for photosynthesis. We suspect that diatoms use the frustule as a complex optical device to collect sunlight and channel it to its chloroplasts to fix carbon dioxide and make oxygen. In our research, we use theoretical models and conduct experiments to show how diatoms are photonic (optical) on a very small scale they are nanophotonic. We show how pattern formation leads to nanophotonic behavior. Magnetism too is the result of patterning of electrons in an ordered way (ferromagnetism is an example). There are unusual fluids ferrofluids that consist of magnetic nanoparticles like magnetite, Fe3O4. When a flat pool of such a fluid is exposed to a magnetic field, a pattern suddenly forms. This breaks the rotational symmetry of the pool, and we call this a phase transition. Symmetry-breaking leads to patterns. We are interested not only in how these patterns form, but how to make permanent records of them. We have discovered a way to do so, and we describe it in this research proposal. Permanent patterns of magnetic material will allow us to create new kinds of magnetism for things like tiny actuators that can be mobilized in magnetic fields to imitate the cilia of micro-organisms or in the human lung. Such a study can impact health research. In the end, the study of patterned structures will tell us something new about how to create new functions of matter that emerge from patterns. It is for these reasons that we entitle our research program, Patterned Hierarchies of Functional Materials.