Synchronization in arrays of vacuum microdiodes

TL;DR

This paper investigates how arrays of small vacuum microdiodes can be synchronized to produce higher power THz signals, leveraging space-charge effects and emitter interactions, with potential applications in high-frequency radiation sources.

Contribution

It demonstrates that synchronized arrays of microdiodes generate higher frequency and power signals than single emitters of the same total area.

Findings

Arrays produce higher frequency signals than single emitters.

Synchronization increases the radiated power.

Modulation frequency can be tuned by emitter parameters.

Abstract

Simulations have shown that space-charge effects can lead to regular modulation of photoemitted beams in vacuum diodes with gap sizes on the order of 1 micron and accelerating voltage on the order of 1V. These modulations are in the THz regime and can be tuned by simply changing the emitter area or accelerating vacuum field. The average current in the diode corresponds to the Child-Langmuir current, but the amplitude of the oscillations is affected by various factors. Given the small size and voltage of the system, the maximum radiated AC power is expected to be small. In this work we show that an array of small emitters produces higher frequency signals than a single large emitter of same area, and how these emitters may be synchronized to produce higher power signals.