Fig. 4
From: Towards integrated tunable all-silicon free-electron light sources
Maximal efficiency of all-silicon tunable sources in the near-infrared. a Calculated efficiency of a single silicon emitter integrated with a silicon nanograting as a function of the electron beam diameter. The insets show the beam shape and alignment configuration with respect to the nanograting in this simulation. b (Illustration) Setup used to theoretically evaluate the maximal efficiency of multiple FEA designs integrated into a SP source. c Calculated upper limit of the optical power as a function of the gate voltage for different FEA designs integrated with a 10 µm long silicon grating. These different designs are all gated with the same range of voltages VGE (20–100 V). The inset shows our experimental results in a modified SEM setup as a function of the electron beam voltage
