The experimental studies of two-dimensional (2D) coaxial Bragg structures are presented. These structures, which realize 2D distributed feedback, have been recently proposed as a method of producing gigawatt power level spatially coherent radiation from a free-electron maser driven by a large-size relativistic electron beam of annular geometry. The experimentally obtained frequency dependence of transmission coefficients for the 2D Bragg structures are in good agreement with theoretical predictions that demonstrates the operation of the two-dimensional Bragg scattering mechanism.
- two-dimensional coaxial Bragg structures
- gigawatt power
- applied physics
- free electron lasers