Bidirectional m/m Transfer Gates for 4 Mb Ion-Implanted Bubble Devices

Roles of a compensation conductor on m/m gates for 4 Mb ion-implanted contiguous disk bubble devices were described. The C-loop to S-loop distance was adjusted for gate operation improvement. The compensation conductor cancelled unnecessary magnetic fields near the gate and reduced propagation errors of bubbles near the gate conductor. Bias margins for consecutive transfer operations have been improved even for long data pages.