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arXiv · 1707.05738

Engineering Er3+ placement and emission through chemically-synthesized self-aligned SiC:Ox nanowire photonic crystal structures

Abstract

High precision placement and integration of color centers in a silicon-based nanosystem, such as a nanowire (NW) array, exhibiting high integration functionality and high photoluminescence (PL) yield can serve as a critical building block towards the practical realization of devices in the emerging field of quantum technologies. Herein, we report on an innovative synthesis route for realizing ultrathin silicon carbide (SiC) NW arrays doped with and without oxygen (SiC:Ox), and also erbium (Er). The arrays of the deterministically positioned NWs are grown in a self-aligned manner through chemical-vapor-deposition (CVD). A key enabler of this synthesis route is that SiC:Ox NW photonic crystal (PC) nanostructures are engineered with tailored geometry in precise locations during nanofabrication. These ultrathin NW PC structures not only facilitate the on-demand positioning of Er3+ ions but are pivotal in engineering the emission properties of these color centers. Through a combinational and systematic micro-PL (uPL) and power-dependence PL (PDPL) spectroscopy, PC architecture geometry effects on Er3+-related 1538 nm emission, which is the telecommunication wavelength used in optical fibers, were studied. Approximately 60-fold and 30-fold enhancements for, respectively, the room-temperature Er3+ PL emission and lifetime in the NW PC sample were observed compared to its thin-film analog. Furthermore, the 1538 nm emission in SiC:Ox NW PC was found to be modulated linearly with the PC lattice periodicity of the structure. The observed characteristics reveal the efficient Er3+-emission extraction from the technologically-friendly SiC:Ox NW PC structures.

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Natasha Tabassum, Vasileios Nikas, Brian Ford, Edward Crawford, Spyros Gallis. 2017-10-26. Engineering Er3+ placement and emission through chemically-synthesized self-aligned SiC:Ox nanowire photonic crystal structures. https://arxiv.org/abs/1707.05738

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