Distinguishing viscous, ballistic, and diffusive current flows in anisotropic metals

  title={Distinguishing viscous, ballistic, and diffusive current flows in anisotropic metals},
  author={Marvin Qi and Andrew Lucas},
  journal={Physical Review B},
We show that in anisotropic Fermi liquids where momentum-conserving scattering is much faster than momentum-relaxing scattering processes, local imaging of the electric current flow patterns can cleanly distinguish between ballistic, viscous and ohmic flow patterns simultaneously (using a single image). We propose using multi-layer graphene-based heterostructures, including ABA trilayer graphene, as a natural experimental platform where an anisotropic ballistic-to-viscous crossover may be… 

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