Laboratoire Charles Coulomb (L2C), Université de Montpellier, CNRS UMR 5221 , 34090 Montpellier, France.
Institut d'Electronique et des Systèmes (IES), Université de Montpellier, CNRS UMR 5114 , 34090 Montpellier, France.
Nano Lett. 2017 Nov 8;17(11):7015-7020. doi: 10.1021/acs.nanolett.7b03625. Epub 2017 Oct 18.
A graphene ballistic rectifier is used in conjunction with an antenna to demonstrate a rectenna as a terahertz (THz) detector. A small-area (<1 μm) local gate is used to adjust the Fermi level in the device to optimize the output while minimizing the impact on the cutoff frequency. The device operates in both n- and p-type transport regimes and shows a peak extrinsic responsivity of 764 V/W and a corresponding noise equivalent power of 34 pW Hz at room temperature with no indications of a cutoff frequency up to 0.45 THz. The device also demonstrates a linear response for more than 3 orders of magnitude of input power due to its zero threshold voltage, quadratic current-voltage characteristics and high saturation current. Finally, the device is used to take an image of an optically opaque object at 0.685 THz, demonstrating potential in both medical and security imaging applications.
一个石墨烯弹道整流器与天线结合使用，作为太赫兹（THz）探测器演示整流天线。使用小面积（<1 μm）的局部栅极来调整器件中的费米能级，以优化输出，同时最小化对截止频率的影响。该器件在 n 型和 p 型传输机制下都能工作，并在室温下显示出 764 V/W 的峰值外量子响应和相应的噪声等效功率 34 pW Hz，没有截止频率高达 0.45 THz 的迹象。由于其零阈值电压、二次电流-电压特性和高饱和电流，该器件还展示了超过 3 个数量级的输入功率线性响应。最后，该器件用于在 0.685 THz 处拍摄一个不透明物体的图像，展示了在医学和安全成像应用中的潜力。
