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Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Hall drag and magnetodrag in graphene
Justin C W Song1, Leonid S Levitov
1Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA and School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
Physical Review Letters
|October 8, 2013
Summary
Strong magnetic fields couple charged and neutral modes in graphene, causing significant magnetodrag and Hall drag due to energy currents and temperature gradients.
Area of Science:
- Condensed matter physics
- Materials science
Background:
- Massless Dirac fermions in graphene exhibit strong interactions.
- Charged and neutral (energy) modes are crucial but typically decoupled.
Purpose of the Study:
- Investigate the coupling of charged and neutral modes in graphene under a magnetic field.
- Explain the origin of strong magnetodrag and Hall drag phenomena.
Main Methods:
- Theoretical analysis of massless Dirac fermions in graphene with a magnetic field.
- Focus on the role of energy currents and temperature gradients.
Main Results:
- Magnetic fields strongly couple charged and neutral modes.
- Observed strong magnetodrag and Hall drag due to long-range energy currents.
- Energy-driven effects show unusual dependence on field and carrier density.
Conclusions:
- The proposed mechanism explains recent observations of giant magnetodrag and Hall drag.
- Energy currents and temperature gradients are key to understanding these phenomena in graphene.
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