Fig. 5: ETVS’s stability to the doping of different energy barriers.
From: Extended topological valley-locked surface acoustic waves
a–c (bottom) Schematics of three heterostructured valley interfaces, when the radius of the micropillars of SMs increasing from a 4.3 μm to b 5 μm to c 5.8 μm. (upper) SAW band structures of the corresponding SMs. Their SAW Dirac frequency decreases inside the VA/VB’s bulk bandgap. (middle) Experimentally measured SAW out-of-plane amplitude distributions crossing the doping areas. SAWs remain highly localized in all these cases. d–f Experiment and simulation SAW out-of-plane displacement distribution (at 76 MHz shown in the figures) depending on different doping.
