Laboratory for Solid State Physics, ETH Zürich, CH-8093 Zürich, Switzerland. Department of Physics, University of California, Berkeley, CA 94720, USA. Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany.
Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany.
Science. 2016 Mar 4;351(6277):1061-4. doi: 10.1126/science.aac8385. Epub 2016 Feb 11.
Electron transport is conventionally determined by the momentum-relaxing scattering of electrons by the host solid and its excitations. Hydrodynamic fluid flow through channels, in contrast, is determined partly by the viscosity of the fluid, which is governed by momentum-conserving internal collisions. A long-standing question in the physics of solids has been whether the viscosity of the electron fluid plays an observable role in determining the resistance. We report experimental evidence that the resistance of restricted channels of the ultrapure two-dimensional metal palladium cobaltate (PdCoO2) has a large viscous contribution. Comparison with theory allows an estimate of the electronic viscosity in the range between 6 × 10(-3) kg m(-1) s(-1) and 3 × 10(-4) kg m(-1) s(-1), versus 1 × 10(-3) kg m(-1) s(-1) for water at room temperature.
电子输运通常由电子与宿主固体及其激发态的动量弛豫散射决定。相比之下，流体在通道中的流动部分取决于流体的粘性，而粘性则由动量守恒的内碰撞决定。固体物理学中长期存在的一个问题是，电子流体的粘性是否在决定电阻方面起着可观察的作用。我们报告了实验证据，表明超纯二维金属钯钴氧化物（PdCoO2）受限通道的电阻具有较大的粘性贡献。与理论的比较允许估计电子粘度在 6×10^(-3)kg m^(-1) s^(-1)和 3×10^(-4)kg m^(-1) s^(-1)之间，而室温下水的粘度为 1×10^(-3)kg m^(-1) s^(-1)。
