Fabrication of a brush-shaped bent fiber probe for near-field optics by heated pulling combined with chemical etching

We developed a method to fabricate bent fiber probe: heated pulling combined with chemical etching. Based on sampling theory, the resolving power of SNOM relates to the size of the probe tip. If the apex of the probe is smaller, the resolution ability of SNOM is higher. At the same time it can collect more near-field information through bigger cone angle of probe. Through improving the operation and optimizing the parameters of the heated-pulling instrument, we can obtain the probe with bent angle fiber varying from 120-150 degree, the cone angle varying from 40-90 degree and the apex diameter less than 100nm. With this new brush shape of probe, the collecting efficiency for near-field light is improved. That is to say that more near-field information is obtained. The successful ratio of the produce is more than 70%.