Magnetoresistance in Mn ion-implanted GaAs:Zn nanowiresShow others and affiliations
2014 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 104, no 15, article id 153112Article in journal (Refereed) Published
Abstract [en]
We have investigated the magnetoresistance (MR) in a series of Zn doped (p-type) GaAs nanowires implanted with different Mn concentrations. The nanowires with the lowest Mn concentration (~0.0001%) exhibit a low resistance of a few kΩ at 300K and a 4% positive MR at 1.6K, which can be well described by invoking a spin-split subband model. In contrast, nanowires with the highest Mn concentration (4%) display a large resistance of several MΩ at 300K and a large negative MR of 85% at 1.6K. The large negative MR is interpreted in terms of spin-dependent hopping in a complex magnetic nanowire landscape of magnetic polarons, separated by intermediate regions of Mn impurity spins. Sweeping the magnetic field back and forth for the 4% sample reveals a hysteresis that indicates the presence of a weak ferromagnetic phase. We propose co-doping with Zn to be a promising way to reach the goal of realizing ferromagnetic Ga1-xMnxAs nanowires for future nanospintronics. © 2014 AIP Publishing LLC.
Place, publisher, year, edition, pages
New York: American Institute of Physics (AIP), 2014. Vol. 104, no 15, article id 153112
Keywords [en]
Nanospintronics, Ion-implantation, GaMnAs, Nanowires, hopping transport, Negative magnetoresistance
National Category
Chemical Sciences Nano Technology
Identifiers
URN: urn:nbn:se:hh:diva-25126DOI: 10.1063/1.4870423ISI: 000335145200060Scopus ID: 2-s2.0-84899622402OAI: oai:DiVA.org:hh-25126DiVA, id: diva2:713170
Funder
Swedish Research CouncilKnut and Alice Wallenberg FoundationSwedish Foundation for Strategic Research
Note
W. Paschoal, Jr. and S. Kumar contributed equally to this work and are co-first authors. The authors acknowledge financial support from nmC@LU, the Swedish Research Council (VR), the Knut and Alice Wallenberg Foundation, the Swedish National Board for Industrial, Technological Development, the Swedish Foundation for Strategic Research, the Nordforsk research network “Nanospintronics; theory and simulations,” and the German Research Society (DFG) Project Ro1198/14. One of the authors, W.P., Jr., gratefully acknowledges financial support from the Pará Education Secretary (SEDUC) and the Pará Government School (EGPA).
2014-04-222014-04-222022-09-13Bibliographically approved