Detectors of high-frequency radiation based on high-electron-mobility transistors benefit from low noise, room-temperature operation, and the possibility to perform radiation spectroscopy using gate-tunable plasmon resonance. Despite successful proof-of-concept demonstrations, the responsivity of transistor-based detectors of terahertz radiation, at present, remains fairly poor. To resolve this problem, we propose a class of devices supporting singular plasmon modes, i.e., modes with strong electric fields near keen electrodes. A large plasmon-enhanced electric field results in amplified nonlinearities, and thus efficient ac-to-dc conversion. We analyse subterahertz detectors based on a two-dimensional electron system in the Corbino geometry as a prototypical and exactly solvable model, and show that the responsivity scales as $1/r_0^2$ with the radius of the inner contact $r_0$. This enables responsivities exceeding 10 kV/W at subterahertz frequencies for nanometer-scale contacts readily accessible by modern nanofabrication techniques.

中文翻译：

---

高迁移率场效应晶体管中的奇异性增强太赫兹检测

基于高电子迁移率晶体管的高频辐射检测器受益于低噪声，室温操作以及使用门可调等离子体激元共振进行辐射光谱的可能性。尽管成功进行了概念验证演示，但目前基于晶体管的太赫兹辐射探测器的响应能力仍然很差。为了解决这个问题，我们提出了一类支持奇异等离激元模式的设备，即在靠近敏锐电极的地方具有强电场的模式。大的等离激元增强电场会导致非线性放大，从而导致有效的AC-DC转换。我们分析了基于Corbino几何中的二维电子系统的太赫兹探测器，作为原型和可精确求解的模型，并表明响应度与$\mathrm{1个}/{\mathrm{[R}}_0^2$ 内触点的半径 ${\mathrm{[R}}_0$。这使得通过现代纳米制造技术可以轻易获得的纳米级触点在太赫兹频率下的响应度超过10 kV / W。