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arXiv · 2107.01216

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

Marvin Qi·Andrew Lucas
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Abstract

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 visible in near-term experiments. Such experiments could lead to more direct measurements of momentum-conserving scattering lengths in electronic Fermi liquids.

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Marvin Qi, Andrew Lucas. 2021-11-18. Distinguishing viscous, ballistic, and diffusive current flows in anisotropic metals. https://doi.org/10.1103/physrevb.104.195106

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