Raman characterization of single-crystalline Ga0.96Mn0.04As:Zn nanowires realized by ion-implantationShow others and affiliations
2019 (English)In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 30, no 33, article id 335202Article in journal (Refereed) Published
Abstract [en]
Recent progress in the realization of magnetic GaAs nanowires (NWs) doped with Mn has attracted a lot of attention due to their potential application in spintronics. In this work, we present a detailed Raman investigation of the structural properties of Zn doped GaAs (GaAs:Zn) and Mn-implanted GaAs:Zn (Ga0.96Mn0.04As:Zn) NWs. A significant broadening and redshift of the optical TO and LO phonon modes are observed for these NWs compared to as-grown undoped wires, which is attributed to strain induced by the Zn/Mn doping and to the presence of implantation-related defects. Moreover, the LO phonon modes are strongly damped, which is interpreted in terms of a strong LO phonon-plasmon coupling, induced by the free hole concentration. Moreover, we report on two new interesting Raman phonon modes (191 and 252 cm −1) observed in Mn ion-implanted NWs, which we attribute to Eg (TO) and A1g (LO) vibrational modes in a sheet layer of crystalline arsenic present on the surface of the NWs. This conclusion is supported by fitting the observed Raman shifts for the SO phonon modes to a theoretical dispersion function for a GaAs NW capped with a dielectric shell. © 2019 IOP Publishing Ltd.
Place, publisher, year, edition, pages
Bristol: Institute of Physics (IOP), 2019. Vol. 30, no 33, article id 335202
Keywords [en]
nanowires, Mn ion implantation, surface optical phonons, spintronics, Raman spectroscopy
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:hh:diva-41450DOI: 10.1088/1361-6528/ab1beaISI: 000468881500001PubMedID: 31018190Scopus ID: 2-s2.0-85067269466OAI: oai:DiVA.org:hh-41450DiVA, id: diva2:1390239
2020-01-312020-01-312024-03-11Bibliographically approved