Fig. 1: Graphite Tesla valves and thermal characterization.
From: A graphite thermal Tesla valve driven by hydrodynamic phonon transport
a, Optical microscope image of graphite Tesla valves in forward (top) and reverse (bottom) directions. Scale bar, 10 μm. b, Schematic of phonon hydrodynamic flows in a graphite Tesla valve in the reverse case. Arrows indicate the paths of the phonon hydrodynamic flows. Inset, schematic of the pump–probe thermoreflectance measurement. c, Example fitting of the experimental curve of the TDTR signal by FEM simulations in a forward structure at 45 K. The thermal conductivity of the graphite Tesla valve was extracted by obtaining the best fit. d, Histogram of recorded thermal decay times during one measurement. e, Temperature distribution in the Tesla valve structure in the forward direction simulated by FEM. a.u., arbitrary units.
