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Projects/Programs

Displaying 26 - 49 of 49

Measuring Light-Matter Interactions in Chip-Based Optical Cavities

Ongoing
A "single emitter" is a structure that exhibits a transition from a high energy state to a low energy state, thereby generating a photon, or light emission. A variety of solid-state single emitters have been discovered or manufactured. One example is a quantum dot, a nanometer-scale structure that

Metrologies for Nanobiomaterials in Artificial Photosynthesis

Completed
A transition to solar fuel will require high-efficiency catalysts that make use of domestic fuel feedstocks with minimal additional energy input. In the past several years, novel water oxidation catalysts from abundant elements have been reported. Catalysts deposited onto a photoactive substrate

Micro- and Nanoelectromechanical Systems

Completed
MEMS/NEMS are enabling technologies that bring new functionalities with the potential to radically transform markets ranging from consumer products to national defense. The meteoric rise of the smartphone is an excellent example, in which MEMS accelerometers, gyroscopes, microphones, displays, and

Micro- and nano-optomechanical systems

Ongoing
Our primary current research direction involves the use of fabricated devices with sub-wavelength periodicity (photonic crystals) as optomechanical elements. Such structures enable a rich variety of devices, including mirrors, polarizers, and filters, in a configuration that couples naturally to

Modeling and Simulation of Nanofabrication (Archived)

Completed
While self-assembly is still in its relative infancy with respect to practical use, with much additional research required to reach maturity, the more widely utilized top-down methods will continue to require advances and modifications to improve current nanomanufacturing techniques. This modeling

Molecular Physiology

Ongoing
In close collaboration with experimentalists, we are seeking to increase the resolution, scope, and throughput of single-biomolecule and ensemble techniques, such as nanopore-based biomolecular analysis, ultrafast vibrational spectroscopy, and FRET, among others. These developments rely heavily on

Multi-Organ Microphysiological Systems

Ongoing
We are developing tissue chips and multi-tissue microphysiological devices that support the culture of multiple tissues with physiologically relevant connections and streams of cell-culture medium. The goal in this project is to construct a device that realistically mimics human metabolism as a

Nanoparticle Tracking for Fluidic Self Assembly (Archived)

Completed
Over the last few decades, scientists have developed a sizable library of nanoscale "building blocks." These nanoparticles have novel thermal, optical, mechanical, and chemical properties relative to their macroscopic counterparts, and organized assemblies of these components promise vast

Nanoplasmonics and Three-Dimensional Plasmonic Metamaterials

Ongoing
Plasmonic materials are composed of metals and insulators that are ordered in geometric arrangements with dimensions that are fractions of the wavelength of light. Research groups are experimenting with a variety of geometric approaches, but all aim to exploit surface plasmons, which are light

Nanostructures for Energy Conversion

Completed
Transportation is the single largest contributor to U.S. carbon dioxide emissions. Moving to an electrically powered transportation system that draws on sustainable energy supplies has the potential to lower transportation costs, reduce greenhouse gas emissions, and help further reduce the nation's

Nanotribology for Nanomanufacturing (Archived)

Completed
Friction and wear are major causes of mechanical failures and dissipative energy losses. These shortfalls account for a significant portion of the annual gross domestic product in the United States, amounting to approximately $800 billion in 2010. It is estimated that tens of billions of U.S

Optofluidic Cytometry

Ongoing
Flow cytometers are commercial instruments that provide rapid multiparameter measurements of single cells, which makes them indispensable in basic research and clinical studies of diseases and drug therapies. Measurements of cellular attributes can include indicators of cell size and shape and well

Photon Drag in Metal Films

Ongoing
The photon-drag (PD) effect is the rectified electrical current in a medium generated by radiation pressure. That is, the optical force delivered to an illuminated metal results in a measurable voltage across the film (Figure, left). For decades, this effect in metals has been understood in terms of

Scanning-electron microscopy

Ongoing
Nanoscale measurements provide necessary feedback for the fabrication of nanoscale structures. However, achieving subnanometer uncertainty is challenging for even the best microscope systems. The challenge is even greater for three-dimensional nanostructures, which often require measurement of

Sensing, Transport, and Simulation

Ongoing
We have recently developed a finite-size scaling approach and special simulation cell aspect ratio—the golden aspect ratio—to enable accurate incorporation of access resistant and bulk diffusion in ionic transport, see the figure. This enables quantitative, and efficient, prediction of ion transport

Single-molecule biosensors

Ongoing
We are developing new tools to investigate the energy landscape of single-molecule sensors. Our goal is to apply a wide-ranging array of technologies to probe the critical physicochemical properties of nanopore biosensors. These properties include the free energy of confinement for polymers as they

Super-resolution optical microscopy

Ongoing
Optical microscopy has been fundamental to science for four centuries, enabling resolution of the microscale. In the last two decades, scientists have made the remarkable discovery that super-resolution methods can extend optical microscopy deep into the nanoscale. It is now possible to detect and

Three-Dimensional Nanometer Metrology

Ongoing
Important physical and chemical properties of nanometer scale devices and structures depend on their shape and size. The benefits of nano are already increasing many applications, and are expected to grow significantly. For these applications, measurement accuracy is a fundamental measurement