Magneto-transport Properties in Magnetic Tunnel Junctions with a Single-crystallineLiF Tunnel Barrier

摘要

In the process of investigating magnetic tunnel junction (MTJ), great efforts have been made to develop crystalline tunnel barriers. To date, giant magnetoresistance (MR) ratios have been observed at room temperature (RT) in epitaxial MTJs with oxide barriers. Lithium fluoride (LiF) would be a suitable candidate for a single-crystalline tunnel barrier because of its small lattice mismatch (Δa/a) with bcc-Fe (∼ 0.4%) when the LiF unit cell is turned by 45° with regard to the Fe unit cell. Furthermore, a recent ab initio calculation for the epitaxial Fe(001)/LiF(001)/Fe(001) structures has predicted very high MR ratios up to 2400% [1]. However, only a few studies on the LiF-based MTJ have been reported [2]. Here, we report on structural and magneto-transport properties of Fe/LiF/Fe MTJs.