Nano-scale organic photonic-structures

通过将亚微米尺寸的孔的周期性阵列限定为薄膜，可以创建其中可以控制光传播的光学材料。通过在这种“光子晶体”中放置一个物理缺陷，就有可能产生一个体积，在这个体积内，光可以非常强烈地局域化(俘获)。这种缺陷被称为“光学纳米腔”。当发光材料被放置在纳米腔中时，可以发生许多令人着迷的物理过程，包括显著增强辐射发射率。虽然通过使用无机半导体来定义纳米腔(或位于纳米腔内的材料)在这方面取得了很大进展，但使用有机材料在这方面所做的工作很少。然而，与无机半导体相比，有机半导体显然具有许多优势；这些优势包括在高空间分辨率下易于加工和构图，以及室温光发射。因此，在这项提议中，我们打算开发两种不同的超高分辨率图案化技术，使我们能够在光学纳米腔内沉积荧光有机材料。这将是光学“有机纳米腔”的首次实现，并将使我们能够探索我们可以预期辐射速率显著增加的结构。如果成功，我们研究的这些结构很可能会对它们的量子光学性质产生重大的基本兴趣。然而，我们相信，有机光学纳米腔可以很好地应用于一系列新兴的纳米技术，包括可以作为超高灵敏度生物或化学分析系统的结构。

By defining a periodic array of sub-micron sized holes into a thin film, it is possible to create an optical material in which the propagation of light can be controlled. By placing a physical defect into such a 'photonic-crystal', it is possible to create a volume within which light can be very strongly localized (trapped). Such defects are termed 'optical nano-cavities'. When a light-emitting material is placed within a nano-cavity, many fascinating physical processes can occur, including a significant enhancement of radiative-emission rates. Whilst much progress has been made on this topic by using inorganic semiconductors to define the nanocavity (or as the material located within the nano-cavity), very little has been done in this respect using organic materials. It is clear however that organic semiconductors have a number of advantages over their inorganic counterparts; these include an ease of processing and patterning at high spatial resolution and room-temperature light emission. In this proposal, we therefore intend develop two different ultra-high resolution patterning techniques that will permit us to deposit fluorescent organic materials within an optical nano-cavity. This will represent the first realisation of an optical 'organic-nanocavity' and will permit us to explore structures in which we can anticipate a significant enhancement of radiative rates. If successful, the structures that we study are likely to be of significant fundamental interest for their quantum optical properties. However we believe that organic optical nano-cavities could well find applications in a range of emerging nanotechnologies, including structures that could act as ultra-high sensitivity biological or chemical assay-systems.