Power enhancement in two-dimensional resonant-tunneling-diode terahertz oscillator arrays with staggered arrangement

We design and fabricate a two-dimensional terahertz oscillator array based on resonant-tunneling diodes. The two-dimensional array utilizes high-efficiency slot resonators as array elements, enabling enhancement in power performance. The two-dimensional arrangement is achieved by the staggered configuration of anti-phase resonant-tunneling diode (RTD) pairs coupled by common resistors, while power combination is enhanced since the RTDs are in opposite orientations. Despite the output power of the 8-element arrays being constrained by non-uniform amplitude distribution, this issue can be mitigated through intensive array scaling, as well as the introduction of metal–insulator–metal capacitors. The fabricated arrays comprising up to eight RTDs exhibit coherent oscillation two-dimensionally, featuring a peak output power of 821 μW at 397 GHz, and maintaining 498 μW at 596 GHz. With improved oscillation uniformity, a linear increase in output power with array scaling-up can be expected, realizing high-power, high-directivity terahertz radiation.