Fig. 1: Schematic of the system under study.
From: Complete tunneling of acoustic waves between piezoelectric crystals
Two piezoelectric solids 1, 2 are separated by a vacuum gap of width d. An incoming acoustic wave from solid 1 (positive z-axis of a laboratory coordinates xyz) with an incident angle θi tunnels across the vacuum gap into solid 2 inside the xz-plane. XYZ describe the intrinsic crystal coordinates, which can be rotated w.r.t. the xyz coordinates.
