A hydrodynamic flow of electrons driven by an oscillating electric field is investigated. It is found that a double-peak profile of the electric current can appear. Such a profile originates from the interplay of viscous and inertial properties of the electron fluid as well as the boundary conditions. The nontrivial profile of the current results in a characteristic stray magnetic field where peaks could also occur in one of the field components. Analytical results are supported by numerical calculations in samples of different geometries such as straight channel, nozzle, and cavity and are found to be qualitatively insensitive to a specific form of the oscillating electric field. In addition, it is shown that nozzle and cavity provide an efficient means to locally enhance or reduce the fluid velocity.
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