Dynamic bubble characteristics in field access devices

Abstract

Some important characteristics of bubble behavior in field access control structures can be obtained directly in a new experimental system. Characteristics such as the phase angle of the drive field and bubble size variation through the structure can be obtained. The experimental system makes use of a mirror spacer combined with photoelectrical indication of the output signal of a moving bubble so as to obtain its position and dimensions. The procedure is illustrated with I-1 investigation of propagating structure. It is also shown how the system determines the characteristics of various propagation control circuits to estimate the degree of nonuniformity in bubble motion and delays in the coordinates of the drive field HR.

High-frequency propagation and failure of asymmetric half-disk field access magnetic bubble device elements

“…A phase lag change as the operating frequency was changed from 100 kHz to 200 kHz was also observed. This observation of phase was also made by Il'yashenko et al [2] using a stroboscopic technique that measures directly the in-plane drive direction as a function of instantaneous bubble position through the device cycle. More recently, Doyle et al [3] investigated the high-frequency characteristics of test loops of gap-tolerant half-disk type structures.…”