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Title: Studies of spin related processes in fullerene C 60 devices
We have investigated spin related processes in fullerene C 60 devices using several experimental techniques, which include magnetic field effect of photocurrent and electroluminescence in C 60 -based diodes; spin polarized carrier injection in C 60 -based spin-valves; and pure spin current generation in NiFe/C 60 /Pt trilayer devices. We found that the ‘curvature-related spin orbit coupling’ in C 60 plays a dominant role in the obtained spin-related phenomena. The measured magneto-photocurrent and magneto-electroluminescence responses in C 60 diodes are dominated by the difference in the g -values of hole and electron polarons in the fullerene molecules. We also obtained giant magneto-resistance of ∼10% at 10 K in C 60 spin-valve devices, where spin polarized holes are injected into the C 60 interlayer. In addition, using the technique of spin-pumping in NiFe/C 60 /Pt trilayer devices with various C 60 interlayer thicknesses we determined the spin diffusion length in C 60 films to be 13 ± 2 nm at room temperature.  more » « less
Award ID(s):
1701427
PAR ID:
10064591
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry C
Volume:
6
Issue:
14
ISSN:
2050-7526
Page Range / eLocation ID:
3621 to 3627
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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