Related Experiment Video
Updated: Jun 22, 2026

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Anomalous thermoelectric transport of Dirac particles in graphene
Peng Wei1, Wenzhong Bao, Yong Pu
1Department of Physics, University of California, Riverside, California 92521, USA.
Abstract:
We report a thermoelectric study of graphene in both zero and applied magnetic fields. As a direct consequence of the linear dispersion of massless particles, we find that the Seebeck coefficient Sxx diverges with 1/sqrt[|n_{2D}|], where n_{2D} is the carrier density. We observe a very large Nernst signal S_{xy} ( approximately 50 microV/K at 8 T) at the Dirac point, and an oscillatory dependence of both Sxx and S_{xy} on n_{2D} at low temperatures. Our results underscore the anomalous thermoelectric transport in graphene, which may be used as a highly sensitive probe for impurity bands near the Dirac point.
Related Concept Videos
Carrier Transport
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
Debye–Huckel–Onsager Conductance Equation
Types of Semiconductors
Carrier Generation and Recombination
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
Semiconductors
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
Fermi Level
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...

