Separating hyperfine from spin-orbit interactions in organic semiconductors by multi-octave magnetic resonance using coplanar waveguide microresonators

Gajadhar Joshi; Richards Miller; Lillie Ogden; Marzieh Kavand; Shirin Jamali; Kapildeb Ambal; Suresh Venkatesh; David Schurig; Hans Malissa; John M. Lupton; Christoph Boehme

doi:10.1063/1.4960158

arXiv · 1603.03807

Separating hyperfine from spin-orbit interactions in organic semiconductors by multi-octave magnetic resonance using coplanar waveguide microresonators

Gajadhar Joshi·Richards Miller·Lillie Ogden·Marzieh Kavand·Shirin Jamali·Kapildeb Ambal·Suresh Venkatesh·David Schurig·Hans Malissa·John M. Lupton·Christoph Boehme

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Abstract

Separating the influence of hyperfine from spin-orbit interactions in spin-dependent carrier recombination and dissociation processes necessitates magnetic resonance spectroscopy over a wide range of frequencies. We have designed compact and versatile coplanar waveguide resonators for continuous-wave electrically detected magnetic resonance, and tested these on organic light-emitting diodes. By exploiting both the fundamental and higher-harmonic modes of the resonators we cover almost five octaves in resonance frequency within a single setup. The measurements with a common pi-conjugated polymer as the active material reveal small but non-negligible effects of spin-orbit interactions, which give rise to a broadening of the magnetic resonance spectrum with increasing frequency.

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Gajadhar Joshi, Richards Miller, Lillie Ogden, Marzieh Kavand, Shirin Jamali, Kapildeb Ambal, Suresh Venkatesh, David Schurig, Hans Malissa, John M. Lupton, Christoph Boehme. 2016-03-11. Separating hyperfine from spin-orbit interactions in organic semiconductors by multi-octave magnetic resonance using coplanar waveguide microresonators. https://doi.org/10.1063/1.4960158

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