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Charge-transfer induced magnetic field effects of nano-carbon heterojunctions.

ABSTRACT: Room temperature magnetic field effects have not been definitively observed in either single-walled carbon nanotubes (SWCNTs) or C?? under a small magnetic field due to their weak hyperfine interaction and slight difference of g-factor between positive and negative polarons. Here, we demonstrate charge-transfer induced magnetic field effects in nano-carbon C??-SWCNT bulk heterojunctions at room temperature, where the mechanism of magnetic field effects is verified using excited state transition modeling. By controlling SWCNT concentrations and interfacial interactions, nano-carbon heterojunctions exhibit tunability of charge-transfer density and room temperature magnetoconductance of 2.8% under 100?mT external magnetic field. External stimuli, such as electric field and photoexcitation, also play an important role in controlling the magnetic field effects of nano-carbon heterojunctions, which suggests that these findings could enable the control of optoelectronic properties of nano-carbon heterojunctions.

SUBMITTER: Qin W

PROVIDER: S-EPMC4141262 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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