Operation of magnetic bubble logic devices

Dual-conductor current access magnetic bubble logic devices have been fabricated using 2 μm lithography on garnet with 2 μm diameter bubbles. The devices include an AND/OR gate, a comparator gate and a switch gate. The operating margins of these gates were measured at 100 K Hz and at 1 MHz with a sampling optical microscope. A 30 Oe operating bias field margin was obtained for all the logic gates. The experimental results are in good agreement with the computer simulation results. The simulated failure modes of operation are discussed.