Dynamic magnetic information storage or retrieval – Head – Hall effect
Patent
1996-11-08
1998-11-10
Heinz, A. J.
Dynamic magnetic information storage or retrieval
Head
Hall effect
257421, 365158, G11B 539, G11C 1100
Patent
active
058353143
ABSTRACT:
Ferromagnetic-insulator-ferromagnetic trilayer junctions show magnetoresistance (JMR) effects ranging from about 16% to several hundred percent at room temperature. Larger effects are observed when the actual tunneling resistance (R.sub.T) is comparable to electrode film resistance (R.sub.L) over the junction area in cross-geometry junction measurements. The geometrically enhanced large JMR can be qualitatively explained by the nonuniform current flow over the function area when R.sub.T is comparable to R.sub.L, in the cross-geometry junction structure. For a fixed junction area, the effective junction resistance (R.sub.J) can be varied from less than 1 ohm to several kilohms by controlling the thickness of the insulating layer or by appropriately selecting ferromagnetic films. The trilayer tunnel junctions of the present invention are nonvolatile, stable and are reproducible.
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U.S. Patent Application Serial No. 08/407,761 filed Mar. 21, 1995 by Jagadeesh S. Moodera, Terrilyn Wong, Lisa Kinder and Robert H. Meservey entitled "Electron Tunneling Device Using Ferromagnetic Thin Films", (Copy not submitted).
Kinder Lisa
LeClair Patrick
Moodera Jagadeesh S.
Nowak Janusz
Heinz A. J.
Massachusetts Institute of Technology
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