Terahertz Antenna Impedance Matched to a Graphene Photodetector
arXiv:2405.06579 · doi:10.1021/acsaelm.4c00870
Abstract
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 . 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.
21 pages, 4 figures
References in corpus (7)
- Thermoelectric and Magnetothermoelectric Transport Measurements of Graphene
- Hydrodynamics of electrons in graphene
- Fast and Sensitive Terahertz Detection Using an Antenna-Integrated Graphene pn Junction
- Thermoelectric Transport of Massive Dirac Fermions in Bilayer Graphene
- Ultrafast, Zero-Bias, Graphene Photodetectors with Polymeric Gate Dielectric on Passive Photonic Waveguides
- Ultralow-noise terahertz detection by p-n junctions in gapped bilayer graphene
- Terahertz rectennas on flexible substrates based on one-dimensional metal-insulator-graphene diodes