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A nonlinear, geometric Hall effect without magnetic field.

ABSTRACT: The classical Hall effect, the traditional means of determining charge-carrier sign and density in a conductor, requires a magnetic field to produce transverse voltages across a current-carrying wire. We demonstrate a use of geometry to create transverse potentials along curved paths without any magnetic field. These potentials also reflect the charge-carrier sign and density. We demonstrate this effect experimentally in curved wires where the transverse potentials are consistent with the doping and change polarity as we switch the carrier sign. In straight wires, we measure transverse potential fluctuations with random polarity demonstrating that the current follows a complex, tortuous path. This geometrically induced potential offers a sensitive characterization of inhomogeneous current flow in thin films.

SUBMITTER: Schade NB

PROVIDER: S-EPMC6900534 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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A nonlinear, geometric Hall effect without magnetic field.

Schade Nicholas B NB Schuster David I DI Nagel Sidney R SR

Proceedings of the National Academy of Sciences of the United States of America 20191118 49

The classical Hall effect, the traditional means of determining charge-carrier sign and density in a conductor, requires a magnetic field to produce transverse voltages across a current-carrying wire. We demonstrate a use of geometry to create transverse potentials along curved paths without any magnetic field. These potentials also reflect the charge-carrier sign and density. We demonstrate this effect experimentally in curved wires where the transverse potentials are consistent with the doping ...[more]

PMID: 31740619

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