Tuning hybrid molecule/magnetic interfaces by defect engineering
Research areas:
Experimental Condensed Matter Physics
Polymer Materials
Project leader:
Wittmann, Angela, Jun.-Prof. Dr.
Johannes Gutenberg University Mainz
Department of Physics (KOMET)
Staudingerweg 7, 55128 Mainz
+49 (0)6131 39 24895
a.wittmann[a]uni-mainz.de
Summary
Doping systems of small molecules and polymers with additives has been shown to be a highly efficient method for varying the charge carrier density over multiple orders of magnitude. While the implications on the charge but also thermal transport within these materials systems are currently being studied extensively, the impact on the hybridization at the interface between the molecules and metallic layers and spin transport mechanisms within the organic semiconductors (OSCs) remains to be unveiled. Recently, hybrid molecule/magnet interfaces have gained significant interest in the field of spintronics. The precise control of structure via synthesis and tunability of electronic properties by structural design make molecules a compelling materials system for systematic studies with unprecedented control of structural and electronic properties. The aim of this project is to utilize the tunability of molecular systems to systematically study spintronic phenomena in hybrid magnetic metal/ OSC devices.
We propose to investigate the effects of interfacial charge transfer and hybridization effects at hybrid
ferromagnetic metal/ OSC interfaces upon doping the OSC via probing the impact on the magnetic properties
of the magnetic thin films by combining magneto-transport experiments with magnetic imaging techniques
based on magneto-optical and scanning nitrogen-vacancy center magnetometry. Furthermore, we will explore the dependence of the effective spin-orbit coupling on the charge carrier density by probing the spin-to-charge conversion efficiency electrically via the inverse spin Hall effect in hybrid devices as a function of doping level. Quantifying the change in spin Hall angle due to adsorption of OSCs will elucidate the impact of defects in the molecular layer on spin-orbit coupling effects at the hybrid interface. Targeted control of the magnetic metal/OSC interface opens an avenue toward tailor-made, tunable, and flexible organic spintronic devices for novel memory and unconventional computing technologies.