Relaxation phenomena in current-induced switching in thin magnetic tunnel junctions

• Type: Article in International Scientific Journal
• Date: 2005

Authors

Ventura, João Oliveira Oliveira (Author) Other; Araújo, João Pedro (Author) FCUP; Carpinteiro, F. C. (Author) Other; Sousa, João Bessa (Author) FCUP; Liu, Yaowen (Author) Other; Zhang, Zongzhi (Author) Other; Freitas, P. P. P Peixeiro (Author) Other

Journal

Title: Journal of Magnetism and Magnetic Materials

Vol. 290

Pages: 1067-1070

ISSN: 0304-8853

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 3 Citations

Other information

Authenticus ID: P-000-42A

DOI: 10.1016/j.jmmm.2004.11.460

Abstract (EN): Recently, reversible resistance (R) changes were observed in thin tunnel junctions (TJ) when a critical electrical current was applied. These changes are called current-induced switching (CIS) and are attributed to electromigration in nanoconstrictions in the insulating barrier. Here, we study the CIS effect on a thin TJ prepared by IBD, displaying a 3.4% R change when a CIS cycle is performed at room temperature. After complete (or half) CIS cycles with adequate maximum currents, we monitored R as a function of time. In both cases a non-monotonic relaxation occurs with two distinct relaxation times, τ(1) ∼ 10min, τ(2) ∼ 10(2) min. First R increases (decreases) rapidly, but then a slow relaxation dominates, reducing (increasing) R. These opposite relaxation processes suggest two independent physical mechanisms acting simultaneously inside the TJ. The physical origin of these effects is discussed.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 4