Design Study of a Metamaterial-Assisted Reltron Oscillator

In the present article, a novel metamaterial-assisted reltron is investigated for vacuum electron device applications. The RF modulation cavity of the proposed device is a metamaterial-assisted side coupled cavity (MSCC). A metamaterial unit cell is used due to its compatibility with the vacuum condition. The electromagnetic behavior of the MSCC is analyzed to find the resonant frequency and its corresponding operating mode. The cold test simulation and measurement is performed to validate the resonant frequency of the MSCC. The RF behavior of the metamaterial-assisted reltron is evaluated using particle-in-cell (PIC) simulation with 250-kV total dc voltage, 280-A beam current, and 0.4-T external magnetic field. The beam present simulation provided the output power of ~35.4 MW at the operating frequency of 2.51 GHz and ~50% device electronic efficiency. The responsiveness of the proposed device to various beam parameters is evaluated using parametric analysis. The proposed device due to its miniaturization and good electronic efficiency shows possible solicitations in various accelerators and high-power microwave (HPM) applications.