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Soft materials known as molecular bottlebrush block polymers comprise a polymer backbone with densely grafted polymer side chains. These materials have attracted much attention for their ability to self-assemble into ordered structures with relatively large periodicities (over 50 nm), which are rarely achieved with simpler linear polymers. However, only self-assembly into lamellar and cylindrical phases has been reported in diblock bottlebrush materials.

A plasmon is the result of light interacting with the surface electrons in materials that meet specific dielectric requirements. Noble metals have long been used as plasmonic materials, yet other materials are capable of supporting surface plasmons. Recent work in the Van Duyne lab has shown that aluminum nanoparticles fabricated using a process known as nanosphere lithography (NSL) display plasmons throughout the UV-vis region.

Objective: To develop novel microfluidic flow cells that allow trapping of single DNA molecules and studies of the binding of sequence-specific probes to the trapped DNA.

The types of grain boundaries that make up the interfacial network within polycrystalline solids influence the properties and performance of the material. The population of grain boundary types is anisotropic, meaning that some of the types are found more frequently than others.

A team from IRG-1, working with collaborators at Argonne National Laboratory and the University of Utah, have demonstrated continuous room-temperature electrical tuning of the thermal conductivity of La0.5Sr0.5CoO3-d by a factor of more than five (a record for a single-step process) via ion-gel gating. Application of a gate voltage in these devices drives a transformation from a metallic perovskite phase to an insulating brownmillerite phase via the formation and migration of oxygen vacancies, realizing the record range of measured thermal conductivities.

The coupling of the magnetic and ferroelectric order in multiferroics produces new excitations of mixed magnetic (magnons) and lattice (phonons) character ; electro-magnons. The investigation of these novel excitations as has revealed that they are activated only through symmetric Heisenberg exchange, even in systems in which the static polarization arises from the relativistic antisymmetric exchange.

A physical hypothesis based on theory and ab initio modeling for the stamping of graphene and few layers graphene (FLG) on silica is presented, and the feasibility of site-specific stamping of FLG patterns is demonstrated experimentally (figure below shows 10-layer FLG pattern stamped on silica). The site-specific nature of the patterned stamps over large areas could enable high-throughput fabrication of future graphene-based integrated devices.

Students from Trenton, NJ participated in PCCM's Princeton University Materials Academy (PUMA), learning about materials science and engineering related to energy sustainability. Working with PCCM faculty Wole Soboyejo and Craig Arnold and their graduate students, the PUMA high school students built their own solar ovens and solar cells from readily available materials, while a guest speaker shared her firsthand experience of the impact of solar cookers in economically and politically devastated regions of the world.

The dynamics of entangled polymer solutions far from equilibrium is, at present, a subject of considerable interest because the "natural" modifications to tube or reptation-based theories have not been successful.Â’  In such systems, polymer molecules are highly entangled, which results in the motion o