Antireflection Coatings on Au Plasmonic Gratings for Infrared Photodetection

作者：Chang, Huiting; Zhang, Chi; Zhao, Fangyuan; Hu, Xinhua^*

来源：Plasmonics, 2015, 10(6): 1519-1524.

DOI：10.1007/s11468-015-9961-y

• Antireflection coating
• Plasmonic grating
• Infrared photodetection
• Quantum well

Based on analytic formulas and numerical simulations, we investigate the enhancement effect of dielectric antireflection coatings on the performance of quantum-well infrared photodetectors (QWIP) with Au grating couplers and operating at 15 mu m. It is found that a simple analytic formula can well estimate the optimal coating thickness. By using a GaAs-coated Au grating with optimal parameters, the absorption can be enhanced by 13 times in the QW active region compared with the reference structure (without Au grating and with an isotropic active region). This enhancement is about three times of that without a dielectric coating. For s-polarized light, a high enhancement (> 5) can occur in a broad range of incident angle (|oee integral|< 60(a similar to)).

• 出版日期2015-12
• 单位复旦大学