Salisbury screen absorbers using epsilon-near-zero substrate. (13th January 2021)

• Record Type: Journal Article
• Authors: Wulan, Qiqige; He, De; Zhang, Tieyan; Peng, Hao; Liu, Lu; Medvedev, Viacheslav V; Liu, Zhijun
• Is Part Of: Materials research express. Volume 8:Number 1(2021)
• Publication Date: 2021-01-13
• Subjects: Salisbury screen -- thin film -- absorption -- phase shift -- infrared; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/abd8a1
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: As a planar resonant structure, Salisbury screen offers a cost-effective way of manipulating electromagnetic waves for both fundamental studies and practical applications in optoelectronics. In this paper, we demonstrate Salisbury screen absorbers using epsilon-near-zero substrate, which reduces the spacer thickness below typical one quarter wavelength limit. Three-layered thin-film absorbers made of SiC substrate, ZnSe spacer layer and top NiCr film are designed and fabricated, which exhibit near-perfect absorption at 11.72 μ m with spacer thickness of about half of a quarter-wavelength. For ideal zero-index material without optical loss, our proposed thin-film absorber simplifies to a two-layered structure even without the spacer layer in theory. These results suggest that epsilon-near-zero materials provide an alternative approach in developing compact planar absorbing structures without involving lithographic patterning.