Omnidirectional Absorber by the Void Plasmon Effect in the Visible Region with Greatly Enhanced Localized Electric Field

Nanoscale Research Letters

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[1] 0000 0000 9389 5210, grid.412022.7, Department of Physics, Nanjing Tech University, 211816, Nanjing, People’s Republic of China;0000 0001 0472 9649, grid.263488.3, College of Electronic Science and Technology, Shenzhen University, 518060, Shenzhen, People’s Republic of China;0000 0001 0472 9649, grid.263488.3, College of Electronic Science and Technology, Shenzhen University, 518060, Shenzhen, People’s Republic of China;0000 0001 0472 9649, grid.263488.3, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, People’s Republic of China;

关键词: Absorbers;    Plasmonics;    Fabry–Perot resonance;    Void plasmons;   

DOI  :  10.1186/s11671-019-2873-6

来源: publisher

【 摘 要 】

We propose and investigate a wide-angle and high-efficiency absorber by using the void plasmon (VP) effect in a Fabry–Perot (FP)-like system, which consists of a perforated metal film and a ground metal plane separated by a dielectric spacer. A hybrid FP/VP resonance mode contributes to the high absorption efficiency. Besides the increased absorption, greatly enhanced localized electric-field intensity at “hot spots” (~ 2284 times) can be achieved. In addition, by varying the thickness of the perforated metal layer and the environmental refractive index, the position of resonance peak can be easily controlled. The proposed absorber can also work as a sensor for detecting the surrounding dielectric constant with the maximum value of the figure of merit (FOM) achieving 3.16 in theory. This work creates an alternative design for high-efficiency absorption devices.

【 授权许可】

CC BY