Spin-tunneling magnetoresistive sensors

Magnetic sensors based on spin-dependent tunneling (SDT) have been theoretically simulated, fabricated, and experimentally tested. In particular, SDT sensors that possess even and odd input-output characteristics have been introduced; designed, and studied. In-depth theoretical analysis of their static and dynamic response characteristics has been carried out. It showed good performance of the even-and the odd-type sensors up to 1 GHz and above 1 GHz, respectively. This holds much promise for ultra-fast magnetic reading. A novel type of a SDT sandwich has been developed, which simplifies the microfabrication procedure. A variety of such SDT structures of different compositions was produced and found to reveal effective coupling interaction. A magnetoresistive effect up to 28 % under magnetic field perpendicular to the easy magnetization axis has been recorded. (C) 2000 Elsevier Science S.A. All rights reserved.