Pressure effect on the magnetization of Sr2FeMoO6 thin films grown by pulsed laser deposition

Abstract

Thin films of Sr2FeMoO6 (SFMO) are grown on SrTiO3 (001) substrates by pulsed laser deposition. The best films provide 3.2μB∕f.u. at 5K, a Curie temperature above 400K, low roughness, high crystallinity, and low splashing. Therefore, the use of such SFMO electrodes in magnetic tunnel junctions patterned with conventional lithography is promising. Pseudomorphic epitaxial growth is obtained for thicknesses under 50nm. Above this thickness the films do not relax homogeneously. A coherent and systematic variation of the magnetization with the deposition conditions is obtained, which highlights a high reproducibility. Under a reasonable O2 partial pressure to avoid parasite phases, the limiting factor for high magnetization is the total pressure or the deposition rate. Therefore, the deposition rate is suspected to have a strong influence on the Fe∕Mo ordering. Highly magnetic samples are obtained under a low gas flow of either a 20% O2+N2 or a 0.3% O2+Ar.

Cation order enhancement in Sr2FeMoO6 by water-saturated hydrogen reduction

“…A topical review on double perovskites by Serrate et al has been published elsewhere. 7 Since the discovery of low-field magnetoresistance at high temperatures in half-metal Sr 2 FeMoO 6 (SFMO), 8 the double perovskite is being studied for spintronic devices exploiting magnetic tunnel junctions (MTJ) 9,10,11 or contact-less potentiometric sensors for the automotive industry. 12 These applications are enabled by the high spin polarization of the conduction band.…”

Growth of Sr2CrReO6 epitaxial thin films by pulsed laser deposition

“…Most of the reported thin film growth efforts have been devoted to the well-studied Sr 2 FeMoO 6 (SFMO) material [5][6][7][8][9][10], and to a similar double-perovskite, Sr 2 CrWO 6 (SCWO) with a lower T C (473 K) [11][12][13][14]. To our knowledge, only the growth of SCRO thin films by magnetron sputtering has been reported in the literature [4,15], although work by pulsed laser deposition (PLD) has been presented and is also available [16].…”

The effect of film thickness on the magnetic and magneto-transport properties of Sr2FeMoO6thin films

“…Fix et al [22,23] have obtained pseudomorphic epitaxial growth in SFMO films on STO substrate when the film thickness is less than 50 nm and fully relaxed films when the thickness is larger than 80 nm. Our earlier results [5] and results from Boucher et al [21], however, do not show pseudomorphic growth nor fully relaxed film even at thicknesses over 100 nm.…”