Electric field control of spin re-orientation in perpendicular magnetic tunnel junctions—CoFeB and MgO thickness dependence

Journal Article · Mon Jul 28 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4891843· OSTI ID:22311208

Meng, Hao; Naik, Vinayak Bharat; Liu, Ruisheng; Han, Guchang ^[1]

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1. Data Storage Institute, A*STAR (Agency for Science Technology and Research), 5 Engineering Drive 1, DSI Building, Singapore 117608 (Singapore)

We report an investigation of electric-field (EF) control of spin re-orientation as functions of the thicknesses of CoFeB free layer (FL) and MgO layer in synthetic-antiferromagnetic pinned magnetic tunnel junctions with perpendicular magnetic anisotropy. It is found that the EF modulates the coercivity (Hc) of the FL almost linearly for all FL thicknesses, while the EF efficiency, i.e., the slope of the linearity, increases as the FL thickness increases. This linear variation in Hc is also observed for larger MgO thicknesses (≥1.5 nm), while the EF efficiency increases only slightly from 370 to 410 Oe nm/V when MgO thickness increases from 1.5 to 1.76 nm. We have further observed the absence of quasi-DC unipolar switching. We discuss its origin and highlight the underlying challenges to implement the EF controlled switching in a practical magnetic memory.

• OSTI ID: 22311208
• Journal Information: Applied Physics Letters, Vol. 105, Issue 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANISOTROPY
ANTIFERROMAGNETISM
BORON COMPOUNDS
COBALT COMPOUNDS
COERCIVE FORCE
CONTROL
EFFICIENCY
ELECTRIC FIELDS
IRON COMPOUNDS
LAYERS
MAGNESIUM OXIDES
MAGNETIC PROPERTIES
MEMORY DEVICES
SPIN ORIENTATION
SUPERCONDUCTING JUNCTIONS
THICKNESS
TUNNEL DIODES
TUNNEL EFFECT