The University of Maryland MRSEC grants ended in September 2013 after 17 years of successful operation. This site remains as a history of the center, but will not be actively maintained.

Undergraduate/Graduate Programs

2009 REU Projects

This list will be updated as projects are finalized.

Synthesis and Electronic Transport Properties of Graphene: Single Graphite Layers

Research Advisor: Dr. Michael Fuhrer

It has recently become possible to synthesize graphene, a single atomic plane of graphite, in the laboratory. Graphene may have many of the advantages of carbon nanotubes for electronic applications: high charge-carrier mobility, high thermal conductivity, small electronic mass, etc. However, extrinsic effects, such as interaction with the substrate and adsorbed molecules, play a large role in determining the properties of graphene. The REU student will learn to synthesize single graphene sheets and fabricate devices from graphene using advanced lithography techniques. The student will address the latest problems in graphene electronics including controlled introduction of adsorbates to graphene in ultra-high vacuum to study impurity scattering, superconductivity, and the Kondo effect; imaging electron transport in graphene via scanned-probe techniques, and/or controlling the electronic device properties via interaction with tailored substrates.

Modeling of Elastic Effects on Crystal Surfaces: How Math Works in the Nano-world

Research Advisor: Dr. Dionisios Margetis

Crystal surfaces are used widely in the fabrication of small electronic devices. A crucial question is how mechanical and other properties of surfaces at large scales are affected by processes at smaller (even atomistic) scales. My research focuses on the description of crystal surfaces by use of equations and computer simulations. My goal is to predict how the shapes of small structures (nanostructures) on surfaces change with time. Important factors that influence these changes are temperature and elasticity, which can be controlled in laboratory experiments. Elastic effects are caused either by external mechanical forces or by the material itself, say in a thin film because of a `mismatch' between the structures of two crystals that are in contact. At large scales, the effect of elasticity can be described by differential equations, which are solved numerically or analytically. At smaller scales, there are more than one ways to describe the effect of elasticity.

One method is to use discrete equations for line defects that drive evolution of surfaces. The REU student will learn different methods of describing crystal surfaces under various conditions of experimental interest. He or she will address the latest problems in solving the related equations numerically by computer and analytically by pen and paper. This work will enable us to compare theory with available experimental data in UMD to help build future electronic devices. Part of this project will involve interactions with Professor Phaneuf and his group.

Templating for Directed Self Organization

Research Advisor: Dr. Ray Phaneuf

The drive toward time-efficient fabrication of extremely high densities of nanometer-scale structures for applications in computing, data storage and sensor arrays has produced intense interest in directed self-assembly and directed self-organization. Although there are multiple possible approaches toward realizing these two related phenomena, the simplest involves the use of a template to select the positions at which nanostructures assemble or evolve. Production of the template itself can involve self-organization or a combination of a lithographic step followed by self-organization. This project will involve experiments and modeling aimed at understanding how competing energetic, kinetic and geometric effects can be tuned to direct self-organization during molecular beam epitaxial growth of gallium arsenide. The student will learn how to characterize evolution of topography during growth using atomic force microscopy, and will interact with a research team carrying out both experiments and kinetic Monte Carlo-based simulations.

Switching of Ferroelectric Domains under an Applied Magnetic Field in Mulitferroic BiFeO₃ Thin Films

Research Advisor: Dr. Lourdes Salamanca-Riba

We are investigating the switching of ferroelectric domains in multiferroic materials under an applied magnetic field. Ferroelectric domains in these materials form by the displacement of ions of opposite charge along opposite directions under an applied electric field. We are investigating the magnetoelectric coupling in BiFeO3 films by the direct observation of the ionic displacement of Fe3+ in the pseudo-perovskite unit cell of BiFeO3 under an applied magnetic field. We are also investigating the role of grain boundaries on the switching mechanism. In addition, we are investigating if there is a gradient in the concentration of Fe3+/Fe2+ across grain boundaries and domain boundaries that could affect the switching behavior of these multiferroic materials. This project will involve the growth of films of BiFeO3 using pulsed laser deposition, characterization of the ferroelectric properties of the films, characterization of the structure by X-ray diffraction and preparation of samples for TEM observation. In this project we will grow a series of films with different oxygen partial pressure and temperature and obtain detailed information of the structure and Fe3+/Fe2+ concentration gradient across domain boundaries and grain boundaries. These results will be related to the ferroelectric and ferromagnetic properties of the films in an attempt to understand the switching mechanism of ferroelectric domains under an applied magnetic field.

Optical Metamaterials

Research Advisor: Dr. H. Dennis Drew

Using modern synthesis techniques it has recently become possible to engineer new artificial materials -metamaterials - based on nano-particles. These materials have novel properties that can find many uses in many fields, including optics and nano-optics. Examples are micro lenses, invisibility cloaks, and ultrahigh spatial resolution imaging systems. The REU student will design new metamaterials and applications of these materials. He/she will also learn to synthesize metamaterials and characterize them with optical measurements. He/she will also work on the theory of these materials based on software that performs finite element calculations of electromagnetic fields.

Development of Cell-Based Sensor Technology for Studying Nanoparticle Toxicity

Research Advisor: Dr. Elisabeth Smela

Given the wide variety and rapid growth of different types of engineered nanomaterials, it is critical to build an understanding of which properties and doses of nanomaterials are associated with toxicity, but such studies are currently time consuming and expensive. We would like to develop a cell-based technology for in vitro rapid screening, and to use this platform to examine a series of model nanoparticles. The technology should allow the performance of multiple tests in parallel on distinct populations of cells, each of which is separately and continuously monitored. This project will begin the setting up of such a micro-system, which will be based on capacitance sensing chips. Capacitance is sensitive indicator of cell attachment and morphology, and thus stress and cytotoxicity.

Liquid Crystal - Nanometer Particle - Surface Termination Interactions

Research Advisor: Dr. Luz Martinez-Miranda

The interaction of liquid crystals with nanoparticles is interesting because understanding it better can lead to better applications, and also, because it can give us insights into the interaction of biomolecules and nanoparticles, since liquid crystals are the phases of the cell walls. We have studied for how this interaction varies as a function of particle size. We want to study it as a function of temperature. We have found evidence of a disordering effect in the ordered phase. Heat capacitance measurements have shown a variation of thermal behavior depending on the termination compound that the nanoparticles are coated with. We are interested in looking at how the disordering effect evolves as a function of temperature and eventually connect these results and the heat capacity results.