High-speed switching or tuning of light in fiber Bragg gratings (FBGs) can be applied to Q-switching, cavity dumping, and pulse picking in a fiber laser, among other applications. Although many options have been used such as bending beams, stretching light with a piezoelectric stack, and using magnetic fields, these techniques are relatively slow (microsecond tuning speeds) and have mechanical durability issues. But researchers at the Joint Research Centre of Photonics of the Royal Institute of Technology (Sweden) and Zhejiang University (Hangzhou, China), and Acreo collaborating within Kista Photonics Research Center (Kista, Sweden), are using electrodes placed within microstructured fibers to cause high-speed electro-optical switching and modulation.