Acoustic-surface-wave disk delay lines

Information can be stored serially in an acoustic beam wrapping about the closed surface of a circular thin disk. Beamguiding may be secured by exploiting a natural interaction between edge curvature and crystal anisotropy. Observations at 41 MHz, on Y-cut and ST-cut disks, demonstrate the feasibility of building isopaustic low-spurious level (57-dB) long 250-µs) disk delay lines.