bubble memory

[′bəb·əl ¦mem·rē] (computer science) A computer memory in which the presence or absence of a magnetic bubble in a localized region of a thin magnetic film designates a 1 or 0; storage capacity can be well over 1 megabit per cubic inch. Also known as magnetic bubble memory.

bubble memory

A storage device built using materials such as gadoliniumgallium garnet which are can be magnetised easily in only onedirection. A film of these materials can be created so thatit is magnetisable in an up-down direction. The magneticfields tend to join together, some with the north pole facingup, some with the south.

When a veritcal magnetic field is imposed on this, the areasin opposite alignment to the field shrink to circles, or'bubbles'. A bubble can be formed by reversing the field in asmall spot, and can be destroyed by increasing the field.

Bubble memory is a kind of non-volatile storage butEEPROM, Flash Erasable Programmable Read-Only Memory andferroelectric technologies, which are also non-volatile, arefaster.

["Great Microprocessors of the Past and Present", V 4.0.0,John Bayko , Appendix C]

bubble memory

An early non-volatile magnetic storage device. Developed by Bell Labs researcher Andrew Bobeck in the 1970s, bubble memory was about as fast as a slow hard disk but it held its content without power. As hard disks greatly improved in the 1980s, bubble memory was abandoned even though it was well suited for rugged applications.

Only a couple of square inches in size, a bubble memory module contained a thin film magnetic recording layer, and globular-shaped bubbles (bits) were electromagnetically generated in circular strings inside this layer. In order to read or write the bubbles, they were rotated past the equivalent of a read/write head.

Bubble Memory

Bubble memory is conceptually a stationary disk with spinning bits.

bubble memory

bubble memory

bubble memory

bub′ble mem`ory

bubble memory

bubble memory

bubble memory

bubble memory