Alfihed Salman, Foulds Ian G, Holzman Jonathan F
School of Engineering, University of British Columbia (UBC), Kelowna, BC V1V 1V7, Canada.
Materials Science Research Institute, King Abdulaziz City for Science and Technology (KACST), Riyadh 11442, Saudi Arabia.
Sensors (Basel). 2021 Apr 30;21(9):3131. doi: 10.3390/s21093131.
This work presents a study of photoconductive (PC) terahertz (THz) emitters based upon varied bow-tie (BT) antenna structures on the semi-insulating (SI) forms of GaAs and InP. The BT antennas have electrodes in the form of a Sharp BT, a Broad BT, an Asymmetric BT, a Blunted BT, and a Doubled BT. The study explores the main features of PC THz emitters for spectroscopic studies and sensors application in terms of THz field amplitude and spectral bandwidth. The emitters' performance levels are found to depend strongly upon the PC material and antenna structure. The SI-InP emitters display lower THz field amplitude and narrower bandwidth compared to the SI-GaAs emitters with the same structure (and dimensions). The characterized Doubled BT structure yields a higher THz field amplitude, while the characterized Asymmetric BT structure with flat edges yields a higher bandwidth in comparison to the sharp-edged structures. This knowledge on the PC THz emitter characteristics, in terms of material and structure, can play a key role in future implementations and applications of THz sensor technology.
这项工作展示了一项基于半绝缘（SI）形式的砷化镓（GaAs）和磷化铟（InP）上的各种蝴蝶结（BT）天线结构的光电导（PC）太赫兹（THz）发射器的研究。BT天线具有尖锐BT、宽BT、不对称BT、钝头BT和双BT形式的电极。该研究从太赫兹场幅度和光谱带宽方面探索了用于光谱研究和传感器应用的PC太赫兹发射器的主要特性。发现发射器的性能水平在很大程度上取决于PC材料和天线结构。与具有相同结构（和尺寸）的SI - GaAs发射器相比，SI - InP发射器显示出更低的太赫兹场幅度和更窄的带宽。与尖锐边缘结构相比，具有特征性的双BT结构产生更高的太赫兹场幅度，而具有平坦边缘的特征性不对称BT结构产生更高的带宽。关于PC太赫兹发射器在材料和结构方面特性的这一知识，在太赫兹传感器技术的未来实施和应用中可发挥关键作用。
