We report that a deionized water etching and thermal annealing technique can be effective for preparing atomically-flat and singly-terminated surfaces of single crystalline SrTiO 3 substrates. After a two-step thermal-annealing and deionized-water etching procedure, topography measured by atomic force microscopy shows the evolution of substrates from a rough to step-terraced surface structure. Lateral force microscopy confirms that the atomically-flat surfaces are singly-terminated. Moreover, this technique can be used to remove excessive strontium oxide or hydroxide composites segregated on the SrTiO 3 surface. This acid-etchant-free technique facilitates the preparation of atomically-aligned SrTiO 3 substrates, which promotes studies on twodimensional physics of complex oxide interfaces.

Scaling out and up are terms increasingly being used to describe a desired expansion of beneficial impacts from agricultural research and rural development. This paper explores strategies for scaling out production and livelihood impacts from proven technologies. We draw on a case study of forages and livestock production in Laos, a Southeast Asian country undergoing rapid economic and agricultural change. A facilitated learning environment stimulated farmers to adapt forages, livestock housing, and animal health practices to their own situations (scaling out). Regular follow-up visits and on-the-job mentoring for extension staff provided institutional support (scaling up). Within 5 years, the number of villages and households using forages and fattening livestock had increased six fold, with a 50% reduction in the time required for farmers to get significant benefits. The paper concludes that scaling out positive impacts from systems change requires field tested and proven technologies, evidence of significant livelihood impacts, fostering of local innovation, competent field staff, effective peer learning, and ongoing institutional support.

Piezoresponse force microscopy imaging in conjunction with first-principles calculations provide strong evidence for room-temperature ferroelectricity in epitaxially stabilized hexagonal TbMnO3 thin films, which in the bulk form are with orthorhombic structure. The obtained results demonstrate that new phases and functional properties of complex oxide materials can be strain-engineered using epitaxial growth.

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Indium tin oxide (ITO) is one of the most widely used transparent conductors in optoelectronic device applications. We investigated the optical properties of ITO thin films at high temperatures up to 800 °C using spectroscopic ellipsometry. As temperature increases, amorphous ITO thin films undergo a phase transition at ~ 200 °C and develop polycrystalline phases with increased optical gap energies. The optical gap energies of both polycrystalline and epitaxial ITO thin films decrease with increasing temperature due to electron-phonon interactions. Depending on the background oxygen partial pressure, however, we observed that the optical gap energies exhibit reversible changes, implying that the oxidation and reduction processes occur vigorously due to the low oxidation and reduction potential energies of the ITO thin films at high temperatures. This result suggests that the electronic structure of ITO thin films strongly depends on temperature and oxygen partial pressure while they remain optically transparent, i.e., optical gap energies > 3.6 eV.