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arXiv · 1012.0895

Memory-bit selective recording in vortex-core cross-point architecture

Young-Sang Yu·Hyunsung Jung·Ki-Suk Lee·Peter Fischer·Sang-Koog Kim
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Abstract

In our earlier work [Appl. Phys. Lett. 92, 022509 (2008)], we proposed nonvolatile vortex random access memory (VRAM) based on the energetically stable twofold ground state of vortex-core magnetizations as information carrier. Here we experimentally demonstrate reliable memory bit selection and low-power-consumption recording in a two-by-two vortex-state dot array. The bit selection and core switching is made by flowing currents along two orthogonal addressing electrode lines chosen among the other crossed electrodes. Tailored pulse-type rotating magnetic fields are used for efficiently switching a vortex core only at the intersection of the two orthogonal electrodes. This robust mechanism provides reliable bit selection and information writing operations in a potential VRAM device.

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Young-Sang Yu, Hyunsung Jung, Ki-Suk Lee, Peter Fischer, Sang-Koog Kim. 2010-12-04. Memory-bit selective recording in vortex-core cross-point architecture. https://doi.org/10.1063/1.3551524

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