Microstructural and magneto-optical characterization of ferrimagnetic multilayered thin-film rare-earth iron garnet heterostructures

Abstract

The continuous demands of the computer industry for increased reliability, portability, and density of storage media, has opened a new chapter in the magnetic recording research, by focusing on the viability of magneto-optical materials for storage. Several materials are considered presently to be at the forefront of this new quest: ternary rare-earth transition-metal alloys (such as GdTbFe or TbFeCo), garnets, and Co/Pt or Co/Pd mutilayers. Of these, the ferrimagnetic garnets, due to their relatively flexible structure, may accommodate a large number of substituting ions, allowing thus for a very good control of their magnetic and magneto-optical properties. The good results obtained during thegrowth of epitaxial superconducting oxide thin films by pulsed laser deposition (PLD), has encouragedus to try this novel deposition technique in the growth of multilayered heteroepitaxial ferrimagneticiron garnet thin films.Superlattice heterostructures consisting of alternating single crystalline ferrimagnetic yttrium-iron-garnet (YIG) and bismuth-iron-garnet (BIG) thin film layers, as well as alternating YIG and europiumsubstituted BIG (EBIG), were deposited on single crystalline (111) paramagnetic gadolinium-galliumgarnet (GGG) substrates.