Magnetic phase transitions in two-dimensional films

尽管一切都有三个空间维度，但在某些情况下，第三个维度是如此之小，以至于一个物体的行为就像它是二维的一样。这方面的一个例子是超薄膜的磁性行为。只有一个原子厚度的磁性原子膜，如铁或镍，可以沉积在非磁性的衬底上。薄膜的磁性受到其二维特性的深刻影响，特别是在可能的稳定磁态、它们的取向和随着温度变化而稳定的范围方面。这项计划旨在研究在超高真空中生长的二维超薄磁性薄膜的磁性，并通过薄膜磁性和激光之间的磁光相互作用来探测。具体的项目包括制备和研究无磁化方向的铁磁性薄膜、具有磁畴图案的铁磁性薄膜和反铁磁性薄膜中的相变。

Even though everything has three spatial dimensions, in some cases the third dimension is so small that an object acts precisely as if it is two-dimensional. An example of this is the magnetic behaviour of an ultrathin film. A film of magnetic atoms, such as iron or nickel, that is only one atom thick can be deposited on a substrate that is non-magnetic. The magnetic behaviour of the film is profoundly affected by its two-dimensionality, especially with regard to the possible stable magnetic states, their orientation, and range of stability as the temperature is changed. This proposal aims to study magnetism in two-dimensional ultrathin magnetic films grown in ultrahigh vacuum and probed by magneto-optical interactions between the film magnetism and laser light. Specific projects involve fabricating and studying phase transitions in ferromagnetic films with no preferred direction of magnetization, with patterns of magnetic domains, and in antiferromagnetic films.