Epitaxial type-I and type-II InAs-AlAsSb core-shell nanowires on silicon

Del Giudice, Fabio; Fust, Sergej; Schmiedeke, Paul; Pantle, Johannes; Döblinger, Markus; Ajay, Akhil; Meder, Steffen; Riedl, Hubert; Finley, Jonathan J. und Koblmüller, Gregor (2021): Epitaxial type-I and type-II InAs-AlAsSb core-shell nanowires on silicon. In: Applied Physics Letters, Bd. 119, Nr. 19, 193102

Abstract

Low-bandgap semiconductor nanowires (NWs) attract considerable interest for mid-infrared (MIR) photonics and optoelectronics, where ideal candidate materials require surface-passivated core-shell systems with large tunability in band offset, lineup, and emission wavelength while maintaining close lattice-matching conditions. Here, we propose and demonstrate epitaxial InAs-AlAsSb core-shell NW arrays on silicon (Si) that offer exceptional control over both the internal strain close to lattice-matching as well as band lineups tunable between type-I and type-II, with almost no analogue in the III-V materials family. We develop direct monolithic growth of high-uniformity InAs-AlAsSb NWs with wide tunability in shell composition and employ correlated Raman scattering and micro-photoluminescence spectroscopy to elaborate the interplay among hydrostatic strain, band lineup, and emission energy of the NW core luminescence tuned from similar to 0.4 to 0.55 eV. Electronic structure calculations further support the experimentally observed tunability between type-I and type-II band lineups. The Si-integrated InAs-AlAsSb NW materials system holds large prospects not only for on-chip MIR photonics but also for other applications including high-speed transistors and NW-based hot carrier solar cells. (c) 2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http:// creativecommons.org/licenses/by/4.0/). https://doi.org/10.1063/5.0065867

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 0003-6951
• Sprache: Englisch