Spin-dependent migration-conduction model for ultra-thin magnetic tunnel junctions

• Type: Article in International Scientific Journal
• Date: 2007

Authors

Yu. G Pogorelov (Author) Other; Lopes, JV (Author) Other; Ventura, JO (Author) Other; Freitas, PP (Author) Other; Ferreira, R (Author) Other; Araujo, JP (Author) FCUP; Sousa, JB (Author) FCUP

Journal

Title: Journal of Magnetism and Magnetic Materials

Vol. 316

Pages: E957-E959

ISSN: 0304-8853

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 0 Citations

Scientific classification

FOS: Engineering and technology > Materials engineering

Other information

Authenticus ID: P-004-7XK

DOI: 10.1016/j.jmmm.2007.03.152

Abstract (EN): Magnetic-tunnel junctions MTJs with ultra-thin (similar to 6-9 angstrom) oxide barriers, having the resistance-area product as low as 1-10 Omega mu m(2), and magnetoresistance as high as similar to 20%, were studied. In the temperature range from 300 to 25 K, they display resistance combined between metallic and activated laws. Under applied currents from 0.1 to 10 mA, the dynamic conductance varies from chaotic to periodic regimes, and the noise power spectrum over times from 10 ms to 10(5) s shows a crossover from 1/f(2) to 1/f behavior, all the features being different for parallel (P) and antiparallel (AP) magnetization of electrodes. A theoretical model is proposed, combining electron tunneling through localized defect states in the barrier and migration of respective defect atoms. A qualitative agreement with the experimental noise spectrum is achieved.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 3