Research on Terahertz Backward-Wave Oscillator Based on Photonic Column Array Slow-Wave Structure

This article explores a photonic column array slow-wave structure (SWS). A 0.28-THz sheet beam backward-wave oscillator (BWO) was designed and simulated by calculating the dispersion, field distribution and particle simulation. When the cathode current density is only 10 A/cm² (the minimum is less than 6 A/cm²), the voltage is 12.5 kV and the magnetic field is 0.5 T, the structure interacts with the sheet beam by immersion and the output power is 435 mW. On the basis of previous work, the SWS was fabricated using Lithography-Galvanoformung-Abformung (LIGA) fabrication technology. The results show that the column array structure can effectively improve the interaction efficiency and reduce the starting current density; and effectively improve the lifespan of terahertz (THz) vacuum electron device (VED) cathodes, which is a viable means of increasing the performance of THz vacuum radiation sources.