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Probing variable range hopping lengths by magneto conductance in carbonized polymer nanofibers.

ABSTRACT: Using magneto transport, we probe hopping length scales in the variable range hopping conduction of carbonized polyacetylene and polyaniline nanofibers. In contrast to pristine polyacetylene nanofibers that show vanishing magneto conductance at large electric fields, carbonized polymer nanofibers display a negative magneto conductance that decreases in magnitude but remains finite with respect to the electric field. We show that this behavior of magneto conductance is an indicator of the electric field and temperature dependence of hopping length in the gradual transition from the thermally activated to the activation-less electric field driven variable range hopping transport. This reveals magneto transport as a useful tool to probe hopping lengths in the non-linear hopping regime.

SUBMITTER: Kim KH

PROVIDER: S-EPMC5862887 | biostudies-other | 2018 Mar

REPOSITORIES: biostudies-other

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Probing variable range hopping lengths by magneto conductance in carbonized polymer nanofibers.

Kim Kyung Ho KH Lara-Avila Samuel S He Hans H Kang Hojin H Hong Sung Ju SJ Park Min M Eklöf Johnas J Moth-Poulsen Kasper K Matsushita Satoshi S Akagi Kazuo K Kubatkin Sergey S Park Yung Woo YW

Scientific reports 20180321 1

Using magneto transport, we probe hopping length scales in the variable range hopping conduction of carbonized polyacetylene and polyaniline nanofibers. In contrast to pristine polyacetylene nanofibers that show vanishing magneto conductance at large electric fields, carbonized polymer nanofibers display a negative magneto conductance that decreases in magnitude but remains finite with respect to the electric field. We show that this behavior of magneto conductance is an indicator of the electri ...[more]

PMID: 29563568

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