Hybrid Interface States and Spin Polarization at Ferromagnetic Metal-Organic Heterojunctions: Interface Engineering for Efficient Spin Injection in Organic Spintronics
2014 (English)In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 24, no 30, 4812-4821 p.Article in journal (Refereed) Published
Ferromagnetic metal-organic semiconductor (FM-OSC) hybrid interfaces have been shown to play an important role for spin injection in organic spintronics. Here, 11,11,12,12-tetracyanonaptho-2,6-quinodimethane (TNAP) is introduced as an interfacial layer in Co-OSCs heterojunctions with an aim to tune the spin injection. The Co/TNAP interface is investigated by use of X-ray and ultraviolet photoelectron spectroscopy (XPS/UPS), near edge X-ray absorption fine structure (NEXAFS) and X-ray magnetic circular dichroism (XMCD). Hybrid interface states (HIS) are observed at Co/TNAP interfaces, resulting from chemical interactions between Co and TNAP. The energy level alignment at the Co/TNAP/OSCs interface is also obtained, and a reduction of the hole injection barrier is demonstrated. XMCD results confirm sizeable spin polarization at the Co/TNAP hybrid interface.
Place, publisher, year, edition, pages
Wiley-VCH Verlag , 2014. Vol. 24, no 30, 4812-4821 p.
IdentifiersURN: urn:nbn:se:liu:diva-110478DOI: 10.1002/adfm.201400125ISI: 000340549900011OAI: oai:DiVA.org:liu-110478DiVA: diva2:746962
Funding Agencies|European Union ; Swedish Research Council; Swedish Research Council (Linneus center); Knut and Alice Wallenberg Foundation2014-09-152014-09-122014-09-15