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以实验可制备的镍、铜纳米线三角有序阵列为模型,用平面波法计算了它们的声子能带,发现了GHz频率的超声子带隙。在XΓ方向镍比铜更容易获得z模态带隙,而在ΓM方向上铜材料更容易激发xy模态的带隙以及在高频区获得更宽的带隙;通过调节填充率,可获得z模态和xy模态共同占据的带隙,正方晶格结构比三角晶格结构更有利于同时获得这两种模态的带隙。
Using the experimentally prepared triangular arrays of nickel and copper nanowires as the model, their phonon energy bands were calculated by the plane wave method and the ultrasonic sub-bandgap at GHz frequency was found. In the XΓ direction, nickel is easier to obtain the z-mode bandgap than copper, whereas in the ΓM direction, the copper material excites the bandgap in the xy mode more easily and the wider bandgap in the high-frequency region; by adjusting the filling rate, The z-mode and x-y modes together occupy a bandgap. The square lattice structure is more advantageous than the triangular lattice structure to obtain the bandgap of both modes simultaneously.