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Magneto-optical garnets are attractive because of their high Faraday rotation and low optical loss in the near infrared. Therefore their use is generally in nonreciprocal devices, i.e., as optical isolators in optical communication. In this paper we present data concerning the deposition of Bi3Fe5O12 (BIG) thin films on (100) and (111) Gd3Ga5O12 substrates using pulsed-laser deposition. Laser-induced processes on the surface of the oxide target used for ablation were analyzed and numerous films were deposited. We found the BIG film quality to be strongly affected by oxygen pressure, laser energy density, and the Bi/Fe film ratio, whereas temperature had a minor influence. We also investigated the BIG-film deposition using a target pressed from metallic Bi and Fe powders and found information on the growth behavior of BIG. We report on details of the film deposition and film properties determined by environmental scanning electron microscopy, energy dispersive x-ray analysis, Rutherford backscattering spectroscopy, and x-ray diffraction. In addition, we determined the Faraday rotation of the films. [ABSTRACT FROM AUTHOR]

Background: Modern implant systems used in the cervical region do not allow for the ingrowth of peri-implant mucosa. The aim of the present study was to use a laser to modify titanium implants used in that region in order to promote mucosa ingrowth, thereby creating a biological barrier against bacterial infection.Methods: A KrF-excimer laser (lambda=248 nm) was used (tau=30 ns, fmax=50 Hz, Emax=1.2 J). Craters were generated, under normal atmospheric conditions or in vacuum, in the polished regions of 18 Frialit 2 implants. Surface analysis was performed using a scanning electron microscope, an energy dispersive X-ray technique, and profile analysis.Results: By adjusting the parameters used, it was possible to create canals with widths of up to 100 microm and depths of 450 microm. Canal morphology was influenced by the laser energy and the surrounding atmospheric conditions. Irradiation with 3,000 pulses (650 mJ per pulse) resulted in rough surfaces under normal atmospheric conditions, whereas these parameters resulted in smooth surfaces in vacuum. The surface chemistry was also influenced by the laser parameters used.Conclusion: Laser-assisted modification of titanium surfaces permits fabrication of 3-D surface modifications. The surface chemistry can also be influenced, depending upon the parameters chosen. Further studies are necessary to evaluate whether ingrowth of mucosa into the canals can be realized. [ABSTRACT FROM AUTHOR]