Terahertz Antenna Impedance Matched to a Graphene Photodetector
Journal article, 2024
Developing low-power, high-sensitivity photodetectors for the terahertz (THz) band that operate at room temperature is an important challenge in optoelectronics. In this study, we introduce a photo-thermal-electric (PTE) effect detector based on quasi-free standing bilayer graphene (BLG) on a silicon carbide (SiC) substrate, designed for the THz frequency range. Our detector's performance hinges on a quasi-optical coupling scheme, which integrates an aspherical silicon lens, to optimize impedance matching between the THz antenna and the graphene p-n junction. At room temperature, we achieved a noise equivalent power (NEP) of less than 300 pW/root Hz. Through an impedance matching analysis, we coupled a planar antenna with a graphene p-n junction, inserted in parallel to the nano-gap of the antenna, via two coupling capacitors. By adjusting the capacitors and the antenna arm length, we tailored the antenna's maximum infrared power absorption to specific frequencies. The sensitivity, spectral properties, and scalability of our material make it an ideal candidate for future development of far-infrared detectors operating at room temperature.
Photothermo-electriceffects
Graphene
Far-infrared
Planar Antenna
Terahertz sensors
Author
François Joint
Chalmers, Space, Earth and Environment, Onsala Space Observatory
Kunyi Zhang
University of Maryland
Jayaprakash Poojali
Univ Maryland, Ctr Nanophys & Adv Mat
Daniel Lewis
University of Maryland
Univ Maryland, Dept Elect & Comp Engn
Michael Pedowitz
University of Maryland
Univ Maryland, Dept Elect & Comp Engn
Brendan Jordan
Univ Maryland, Dept Elect & Comp Engn
University of Maryland
Gyan Prakash
University of Maryland
Ashraf Ali
University of Maryland
Kevin Daniels
University of Maryland
Univ Maryland, Dept Elect & Comp Engn
Rachael L. Myers-Ward
US Naval Res Lab
Thomas E. Murphy
University of Maryland
Howard D. Drew
Univ Maryland, Ctr Nanophys & Adv Mat
ACS APPLIED ELECTRONIC MATERIALS
2637-6113 (eISSN)
Vol. In PressSubject Categories
Other Electrical Engineering, Electronic Engineering, Information Engineering
DOI
10.1021/acsaelm.4c00870