Electron viscosity, current vortices and negative nonlocal resistance in graphene
APA
Falkovich, G. (2016). Electron viscosity, current vortices and negative nonlocal resistance in graphene. Perimeter Institute. https://pirsa.org/16040067
MLA
Falkovich, Gregory. Electron viscosity, current vortices and negative nonlocal resistance in graphene. Perimeter Institute, Apr. 26, 2016, https://pirsa.org/16040067
BibTex
@misc{ pirsa_PIRSA:16040067, doi = {10.48660/16040067}, url = {https://pirsa.org/16040067}, author = {Falkovich, Gregory}, keywords = {Condensed Matter}, language = {en}, title = {Electron viscosity, current vortices and negative nonlocal resistance in graphene}, publisher = {Perimeter Institute}, year = {2016}, month = {apr}, note = {PIRSA:16040067 see, \url{https://pirsa.org}} }
Quantum-critical strongly correlated electron systems are predicted to feature universal collision-dominated transport resembling that of viscous fluids. Investigation of these phenomena has been hampered by the lack of known macroscopic signatures of electron viscosity. Here we identify vorticity as such a signature and link it with a readily verifiable striking macroscopic DC transport behavior. Produced by the viscous flow, vorticity can drive electric current against an applied field, resulting in a negative nonlocal voltage. The latter may play the same role for the viscous regime as zero electrical resistance does for superconductivity. Besides offering a diagnostic which distinguishes viscous transport from ohmic currents, the sign-changing electrical response affords a robust tool for directly measuring the viscosity-to-resistivity ratio. Strongly interacting electron-hole plasma in high-mobility graphene affords a unique link between quantum-critical electron transport and the wealth of fluid mechanics phenomena.
Levitov and Falkovich, Nature Physics, 22 Feb 2016