Depth resolved properties of nanoscopic heterostructures using ß-NMR

当材料结合时，不是通过形成化合物，而是形成异质结构（在最简单的例子中，一种材料在另一种材料的衬底上形成薄膜），所得到的性质可能与每一种纯散装起始材料的性质有很大不同。这种“超材料”在电子和传感器方面有着重要的应用，新开发的超材料可能具有前所未有的特性，这些特性可能构成全新技术的基础，如量子计算机或自旋电子学。同样，在自由表面上，材料的性质也不同，例如，在表面重建中，表面原子的晶体结构与简单截短体的晶体结构不同。这种影响可以（而且通常确实）在地表下传播。因此，自由表面附近的超材料和晶体的性质与深度有关。人们对这种现象所知甚少，主要是因为可用的深度分辨技术很少。该提案旨在利用加拿大粒子与核物理国家实验室（TRIUMF）的低能β探测核磁共振技术，作为固体材料的一种新的深度分辨（纳米尺度，即十亿分之一米）实验探针，解决纳米结构超材料中的磁性和超导性等基本和实际问题。离子在固体中的扩散运动是另一个实际重要的特性（例如在固态电化学电池中），它在界面或自由表面附近被修改（并且与深度有关）。该提案还旨在研究分离探针离子在这种情况下的扩散。

When materials are combined, not through formation of a compound, but instead into a heterostructure (in the simplest instance, a thin film of one material on a substrate of another) the resulting properties may differ substantially from those of each of the pure bulk starting materials. Such "metamaterials" have important applications in electronics and sensors, and newly developed metamaterials can have unprecedented properties which may form the basis of entirely new technologies, such as quantum computers or spintronics. In a similar way, the properties of materials differ at a free surface, for example, in surface reconstruction, the crystal structure of atoms at the surface is different from that of a simple truncation of the bulk. Such effects can (and generally do) propagate below the surface. Thus, the properties of metamaterials and crystals near a free surface are depth dependent. Remarkably little is known about such phenomena, mainly because very few depth-resolved techniques are available. This proposal aims to use the technique of low energy beta detected nuclear magnetic resonance at TRIUMF, Canada's National Lab for Particle and Nuclear Physics, as a new depth-resolved (at the nanometer scale, i.e. one billionth of a meter) experimental probe of solid materials, addressing fundamental and practical questions in, for example, magnetism and superconductivity in nanoscopically structured metamaterials. The diffusive motion of ions in solids is another practically important property (for instance in solid state electrochemical batteries) that is modified (and depth-dependent) in the vicinity of an interface or free surface. The proposal also aims to study diffusion of the isolated probe ions in this context.