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A central goal of IRG-4 is to use collective interactions between dissimilar nanocrystals to enhance the performance of their assemblies. Here we demonstrate plasmonic enhancement of optical upconversion luminescence within nanorod-nanophosphor heterodimers (Fig 1a-c). Using experiment and theory we are able to develop design rules for optimizing heterodimer geometry. The templated assembly process (Fig 1d-e) can be used for many other nanocrystal building blocks and for larger assemblies.

In 2015 we will celebrate the arrival of our 600th REU student in our U.S. National Science Foundation-supported REU program. This program started in 1989 with a small grant that supported 5 minority students. Over the following 26 years, we have averaged 23 students/yr by supplementing our MRSEC–supported students with an additional DMR REU Site grant that supported 10 students per year and some individual faculty contributions. Overall, 61% of our students were from under-represented groups (39% minority and 43% women) in STEM departments.

Crystalline silicon is a critically important electronic material in all consumer electronic products.   The ability to create fibers from this material would open up exciting vistas for a new generation of fiber-based electronic and optical devices.  Traditional fiber-optic drawing involves a thermally mediated geometric scaling where both the fiber materials and their relative positions are identical to those found in the fiber preform. To date, all thermally drawn fibers are limited to the preform composition and geometry.

Molecules with switchable magnetic moment could become of considerable importance for the emerging field of organic spintronics, where the control of spin degrees of freedom may be performed electrically on the molecular scale.  Spin crossover complexes based on magnetic iron (Fe) ions are interesting in this regard because they exhibit a reversible transition between a high-spin and low-spin magnetic state, which can be induced by external stimuli such as temperature, pressure, electric field, and by light.

During the summer of 2015, Research Experiences for Teachers (RET) participant Courtney Matulka of Millard Public Schools together with Seed Project leader Krista Adams and Professor-Student Pairs participant Sharmin Sikich of Doane College developed a video blog, or “vlog,” to highlight the cutting-edge research happening in the nanosciences at the University of Nebraska-Lincoln (UNL). Working with Nebraska MRSEC Education/Outreach Director Axel Enders, Matulka interviewed and filmed Nebraska MRSEC faculty and Professor-Student

Researchers at OSU's Center for Emergent Materials have established a novel route for growing precise layers of optoelectronic 2D materials directly onto wafers commonly used by the semiconductor industry. This route combines the epitaxial growth of a crystalling precursor lattice (CaGe2) with its conversion into a layered 2D material (GeH) phase.

Chromonic liquid crystals (CLCs) are different from typical LCs used in displays, in part because they “live” in water and thus hold untapped potential for coupling LC phenomenology with biological media. Furthermore, CLCs twist very easily compared to bend and splay deformation, and the consequences of this giant elastic anisotropy are not well understood. Recently, Collings, Lubensky, Yodh & Johnson developed a new alignment layer for CLCs based on parylene (Fig. 1); it enabled homeotropic surface anchoring (i.e., perpendicular anchoring) [1].  

Whether metallic behavior can exist in 2D materials is a question that has troubled condensed matter physics for decades. Although originally thought impossible, evidence for such in ultra-clean high-purity doped inorganic semiconductor heterostructures based on materials such as Si and GaAs eventually changed the prevailing view. 

In a paper published in Nature Materials, researchers from North Carolina State University and the University of North Carolina-Chapel Hill show that magnetic nanoparticles encased in oily liquid shells can bind together in water, much like sand particles mixed with the right amount of water can form sandcastles.