More on High-Gradient Insulators

High-Gradient Insulators (HGI) are periodic structures made up of metal and insulator layers. HGI´s are superior to ordinary insulators as they break down in vacuum at 2- 4 times higher applied voltages. Recently a model has been proposed which explains flat surface HGI behavior. The model and experiments have been extended here to coned flat surface HGI´s. We have constructed such HGI´s and found that their behavior follows our model predictions.