A new-ultra-density solid state memory: Bloch line memory

A new magnetic solid state memory is proposed, which utilizes usual bubble garnet films. The "1" or "0" is stored by the presence or absence of a negative vertical Bloch line pair in the stripe domains. The memory chip organization is composed of a conductor-drive bubble-propagation major line and long stripe domains aligned in parallel which constitute minor loops to accommodate vertical Bloch line pairs. When doing the writing, the presence and absence of the bubbles in the major line is converted to the presence and absence of the vertical Bloch line in the storage area. When doing the reading, the reverse is true. The Bloch line pair is replicated in the stripe domains, and the converted bubbles are detected by the usual stretcher detector. The Bloch lines propagate under the successively applied bias pulsed fields. The bit density increases drastically, and we can expect around 1.6 Gbit/cm2using 0.5 μm bubble garnet films.