Pseudo surface wave on the (1012) plane of sapphire

The present article demonstrated that pseudo surface wave (PSW) should exist on a slightly anisotropic crystal sapphire. PSW velocity dispersions on the three principal planes of sapphire were numerically calculated. The existence possibility of PSW on the water-sapphire (1012) plane was experimentally examined by using acoustic spectromicroscopy. Numerical analysis reveals that the two-component surface wave should be activated on the sapphire (1012) plane along direction angle φ₀=17.18631°. This also verified the existence possibility of PSW on the slightly anisotropic crystal sapphire.