Metal-Semiconductor AsSb-Al0.6Ga0.4As0.97Sb0.03 Metamaterial

Abstract

AlGaAsSb and AlGaAs films as thick as 1 μm with Al content as high as 60% were successfully grown by low-temperature (200 °C) MBE. To overcome the well-known problem of growth disruption due to a high aluminum content and a low growth temperature, we applied intermittent growth with the temperature elevation to smooth out the emerging roughness of the growth front. Post-growth annealing of the obtained material allowed us to form a developed system of As or AsSb nanoinclusions, which occupy 0.3–0.6% of the material volume. While the As nanoinclusions are optically inactive, the AsSb nanoinclusions provide a strong optical absorption near the band edge of the semiconductor matrix due to the Fröhlich plasmon resonance. Owing to the wider bandgap of the grown Al0.6Ga0.4As0.97Sb0.03 compound, we have expanded the spectral range available for studying the Fröhlich plasmon resonance. The grown metamaterial represents an optically active medium of which the formation process is completely compatible with the epitaxial growth technology of semiconductors.

Unveiling Influence of Dielectric Losses on the Localized Surface Plasmon Resonance in (Al,Ga)As:Sb Metamaterials

“…The Sb nanoparticle radius is taken as 3.1 nm, and the filling factor f = 0.016. These values correspond to the results of the experimental structural studies of Sb-enriched nanoinclusions formed in GaAs(Sb), Al 0.3 Ga 0.7 As(Sb), and Al 0.6 Ga 0.4 As(Sb) [23,24]. It is evident from Figure 4 that the Sb nanoparticle system embedded in the Al x Ga 1−x As matrix forms a band of resonant light absorption in the optical spectra, which is due to LSPR.…”

“…It is important to note that the results of the above-described modeling of the optical spectra are fully consistent with the existing experimental data obtained for metamaterials with Sb-rich AsSb nanoinclusions built in GaAs, Al 0.3 Ga 0.7 As, and Al 0.6 Ga 0.4 As semiconductor matrices [21][22][23][24].…”

Structure and optical properties of a composite AsSb-Al-=SUB=-0.6-=/SUB=-Ga-=SUB=-0.4-=/SUB=-As-=SUB=-0.97-=/SUB=-Sb-=SUB=-0.03-=/SUB=- metamaterial

“…The results of structural studies obtained in this work allow us making a conclusion about the strong segregation of antimony in nanoinclusions formed in the studied metamaterial based on Al 0.6 Ga 0.4 As 0.97 Sb 0.03 . It is not possible to quantify the exact antimony concentration in nanoinclusions immersed in the matrix, however, the enrichment turned out to be strong enough for reliable detection using EDXS method [17] which is ensured with antimony concentrations of 50% or more. The concentration of Sb in nanoinclusions exceeded 90% in the previously studied metamaterial based on Al 0.3 Ga 0.7 As 0.97 Sb 0.03 .…”

Структура и оптические свойства композитного метаматериала AsSb-Al-=SUB=-0.6-=/SUB=-Ga-=SUB=-0.4-=/SUB=-As-=SUB=-0.97-=/SUB=-Sb-=SUB=-0.03-=/SUB=-

“…Полученные в данной работе результаты структурных исследований позволяют сделать заключение о сильной сегрегации сурьмы в нановключениях, формирующихся в исследуемом метаматериале на основе Al 0.6 Ga 0.4 As 0.97 Sb 0.03 . Количественно точно определить концентрацию сурьмы в нановключениях, погруженных в матрицу, не представляется возможным, однако обогащение оказалось достаточно сильным для надежного детектирования методом EDXS [17]…”