Pulsed laser deposition of Y3Fe5O12 and Bi3Fe5O12 films on garnet substrates

Abstract

We prepared Y3Fe5O12 (YIG) and Bi3Fe5O12 (BIG) films by pulsed laser deposition and present some practical aspects here. Low laser repetition rates result in a loss of oxygen and reduce the saturation magnetization of YIG by a factor of 5. Small changes of deposition conditions and lattice match for BIG films have little influence on the spectra of Faraday rotation but change magnetic coercivities by a factor of 10. Thin BIG films show higher coercivities than thick films. Coercivities increase with lattice mismatch between film and substrate. The wavelength of maximum Faraday rotation for BIG films in visible light depends on film thickness: We observed a redshift of almost 40 nm for a 2.6 μm thick film as compared to a 470 nm thick film.

Curie temperature, exchange integrals, and magneto-optical properties in off-stoichiometric bismuth iron garnet epitaxial films

“…A value of −25°/ m for the specific Faraday rotation was observed at a photon energy of 2.25 eV confirming literature results. 25,29,33 The largest specific Faraday rotation ͑ϳ34°/ m͒ was observed for an energy of 2.76 eV. The measured spectral variation agrees well with the results of Chern et al 21 for Y 3−x Bi x Fe 5 O 12 ͑0.5Յ x Յ 3.0͒ films deposited by PLD.…”

“…Figure 8 shows the specific Faraday rotation for all films in the spectral range of 1.9 to 2.4 eV. Films B, D, and E exhibit the same spectral variation with a pronounced peak at ϳ2.32 eV, whereas this peak occurs at lower energies of ϳ2.27 eV for films A and C. It must be pointed out that films A and C are somewhat thicker than films B, D, and E. A qualitatively similar red shift was observed by Kahl et al 25,26 when increasing the thickness of BIG films grown in otherwise identical conditions. These authors could not identify the cause of this apparent thickness dependence of the red shift, although a possible correlation with the x-ray coherence length was detected by x-ray diffraction.…”

“…[11][12][13][14][15][16][17][18][19] However, studies on the role of bismuth in iron garnets have long been confined to compounds with relatively low bismuth content because the pure bismuth iron garnet Bi 3 Fe 5 O 12 ͑BIG͒ does not exist in bulk form ͑due to the large ionic radius of the Bi 3+ cation͒ and cannot be grown by liquid-phase epitaxy ͑LPE͒. Since 1989, several authors have shown that BIG can be grown as a thin film on suitable garnet substrates by pulsed laser deposition ͑PLD͒, 4,6,18,[20][21][22][23][24][25][26][27][28] reactive ion-beam sputtering ͑RIBS͒ ͑Refs. 29-31͒, or other vapor deposition techniques.…”

Pulsed Laser Deposition and Growth Studies of Bi3Fe5O12 on Gd3Ga5O12 and SiO2

“…In comparison to YIG the rotation exhibits a negative sign. Like it is reported in literature 9) and a maximum can be found around 600nm, which is clearly above the FR of YIG. Thereby it turned out that the Bi content within the film is a crucial point (Fig.…”

Pulsed laser deposition of epitaxial yttrium iron garnet films with low Gilbert damping and bulk-like magnetization

“…The film properties presented here represent significant improvements in microstructural and magnetic properties in YIG with respect to earlier studies. 26,27 The results of this study will help in the development of magnonic logic devices, sensors, and other devices to transport, store, and process microwave and digital information with low power and at high density, and in studies of fundamental magnetic phenomena such as spin-Seebeck effect, 28 magnetization dynamics, domain wall dynamics, proximity effects, 29 or on-chip quantum teleportation mechanisms.…”