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تسجيل مستخدم جديدSpin hydrodynamic generation in graphene
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Graphene hosts an ultra-clean electronic system with electron-electron collisions being the dominant source of scattering above liquid nitrogen temperatures. In this regime, the motion of the electron fluid resembles the flow of classical liquids and gases with high viscosity. Here we show that such a viscous electron flow can cause the generation of a spin current perpendicular to the direction of flow. Combining the Navier-Stokes equations and the spin diffusion equation in the presence of the spin-vorticity coupling, we derive an expression for the spin accumulation emerging purely as a result of the viscous electron flow. We explore Poiseuille flow and Jeffery-Hamel flow and show that the spin Hall angle may exceed 0.1 over a wide range of temperatures and can be controlled by carrier density, temperature, and the geometry of sample boundaries. Our theory points to new functionality of graphene as a spin current source.
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Collective behavior is one of the most intriguing aspects of the hydrodynamic approach to electronic transport. Here we provide a consistent, unified calculation of the dispersion relations of the hydrodynamic collective modes in graphene. Taking int
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The demand for compact, high-speed and energy-saving circuitry urges higher efficiency of spintronic devices that can offer a viable alternative for the current electronics. The route towards this goal suggests implementing two-dimensional (2D) mater
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