Microwave

Quantum mechanics

Voltage

Beam (structure)

Engineering

Materials science

Metamaterial

Power (physics)

Amplifier

Computer science

Physics

Optics

Miniaturization

Electronic engineering

Klystron

CMOS

Optoelectronics

Electrical engineering

IEEE Electron Device Letters

A miniaturized, high electronic efficiency, S-band metamaterial extended interaction klystron (MEIK) is proposed. The metamaterial-based extended interaction resonant cavities were designed, fabricated, and tested, the assembled and cold-tested results confirm the feasibility of miniaturization in MEIK. Furthermore, the particle-in-cell (PIC) simulation predicts that, typically, when the beam voltage and current are 30 kV and 3 A, respectively, the focusing magnetic field is 1000 G, a 3-cavity MEIK yields the output power of 56 kW at 2.453 GHz, with the saturated gain of 47 dB and the electronic efficiency of 62%, and, importantly, with the cavity diameter of its interaction structure being ~1/2 of a conventional extended interaction klystron. As a power amplifier, the emerging MEIK with its miniaturization and high electronic efficiency has potential applications such as in future accelerators and microwave heating systems.

Novel S-Band Metamaterial Extended Interaction Klystron