We report the generation of room temperature microwave oscillations from GaN/AlN resonant tunneling diodes, which exhibit record-high peak current densities. The tunneling heterostructure grown by molecular beam epitaxy on freestanding GaN substrates comprises a thin GaN quantum well embedded between two AlN tunneling barriers. The room temperature current-voltage characteristics exhibit a record-high maximum peak current density of ∼220 kA/cm2. When biased within the negative differential conductance region, microwave oscillations are measured with a fundamental frequency of ∼0.94 GHz, generating an output power of ∼3.0 μW. Both the fundamental frequency and the output power of the oscillator are limited by the external biasing circuit. Using a small-signal equivalent circuit model, the maximum intrinsic frequency of oscillation for these diodes is predicted to be ∼200 GHz. This work represents a significant step towards microwave power generation enabled by resonant tunneling transport, an ultra-fast pr...

中文翻译：

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峰值电流密度高达 220 kA/cm2 的 GaN/AlN 谐振隧道二极管中的室温微波振荡

我们报告了 GaN/AlN 谐振隧道二极管产生的室温微波振荡，其表现出创纪录的峰值电流密度。通过分子束外延在独立 GaN 衬底上生长的隧道异质结构包括嵌入两个 AlN 隧道势垒之间的薄 GaN 量子阱。室温电流-电压特性表现出创纪录的最大峰值电流密度，约为 220 kA/cm2。当在负微分电导区域内偏置时，微波振荡以~0.94 GHz 的基频进行测量，产生~3.0 μW 的输出功率。振荡器的基频和输出功率都受到外部偏置电路的限制。使用小信号等效电路模型，这些二极管的最大固有振荡频率预计为~200 GHz。这项工作代表了通过共振隧道传输实现微波发电迈出的重要一步，这是一种超快速...