A new magnetic material with appreciable optical transmission in the visible region at room temperature has been isolated as a gamma-Fe(2)O(3)/polymer nanocomposite. The synthesis is carried out in an ion-exchange resin at 60 degrees C. Magnetization and susceptibility data demonstrate loading-dependent saturation moments as high as 46 electromagnetic units per gram and superparamagnetism for lower loadings where particle sizes are less than 100 angstroms. Optical absorption studies show that the small-particle form of gamma-Fe(2)O(3) is considerably more transparent to visible light than the single-crystal form. The difference in absorption ranges from nearly an order of magnitude in the "red" spectral region to a factor of 3 at 5400 angstroms. The magnetization of the nanocomposite is greater by more than an order of magnitude than those of the strongest room-temperature transparent magnets, FeBO(3) and FeF(3).

Gallium Oxide has undergone rapid technological maturation over the last decade, pushing it to the forefront of ultra-wide band gap semiconductor technologies. Maximizing the potential for a new semiconductor system requires a concerted effort by the community to address technical barriers which limit performance. Due to the favorable intrinsic material properties of gallium oxide, namely, critical field strength, widely tunable conductivity, mobility, and melt-based bulk growth, the major targeted application space is power electronics where high performance is expected at low cost. This Roadmap presents the current state-of-the-art and future challenges in 15 different topics identified by a large number of people active within the gallium oxide research community. Addressing these challenges will enhance the state-of-the-art device performance and allow us to design efficient, high-power, commercially scalable microelectronic systems using the newest semiconductor platform.

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γ-Fe2O3 nanocrystals have been synthesized in a polymer matrix by an ion exchange and precipitation reaction. The particles are crystalline with a mean diameter of 85 Å. The unit cell volume is 1735.2 Å3 corresponding to a unit cell compression of 0.35%. Magnetization and susceptibility data from experiment and computer simulations indicate that the system is superparamagnetic. The calculated magnetic anisotropy for the particles is two orders of magnitude larger than that of bulk γ-Fe2O3 . The optical absorption edge is red shifted with respect to that of an epitaxially grown single-crystal film of γ-Fe2O3 . The red shift is attributed to lattice strain in the small particles.

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