The simulation on absorption properties of metamaterial/GaAs/electrode layer hybrid structure based Terahertz photoconductive detector
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Terahertz (THz) photodetectors have attracted great attention from scientists worldwide for their application in security checking, biomedical treatment and astronomical observation of remote stars and distant galaxies. As a typical THz detector, extrinsic GaAs based photoconductive detector is facing critical technical bottlenecks in the epitaxial growth of sufficiently thick and high-quality GaAs absorption layer. In this work, a novel THz photoconductive detector based on metamaterial/GaAs/electrode layer hybrid structure was designed and simulated. By setting the periodic split ring resonator (SRR) structure as 88 μm pitch with 8 μm width, the absorption peaks exist at the wavelength of about 142 and 367 μm, which originate from the resonant cavity and the SRR dipole resonance effect, and the novel device shows a significant enhancement compared with the conventional GaAs photoconductive detector. Thus, the necessary thickness of GaAs absorption-layer is largely reduced, and the resonant absorption peak can be modulated by changing the thickness of absorption layer. This work provides a novel device structure which can solve the critical epitaxial growth bottleneck of GaAs photoconductive detector and used for the astronomical observation, security check, etc.
KeywordsGaAs photoconductive detector Metamaterial Absorption Periodic split ring resonator (SRR) Dipole resonance
This work was supported by the National Natural Science Foundation of China (Grant Nos. 61705201, and 61404120), Shanghai Rising-Star Program (Grant No. 17QB1403900), Young Elite Scientists Sponsorship Program by CAST (Grant No. 2018QNRC001), Shanghai Sailing Program (Grant No. 17YF1418100), and Shanghai Youth Top-Notch Talent Development Program.
- Zhang, C., Wang, B., Chen, Y., Hou, L., Pan, M., and Wang, X.: Study on the spectral response characteristics of GaAs-based Blocked-Impurity-Band Detectors. ICICM, 105–109 (2017)Google Scholar