Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Engineering

Nano-Structured Materials For Imaging Polarimetry, Andrew Sarangan Oct 2008

Nano-Structured Materials For Imaging Polarimetry, Andrew Sarangan

Andrew Sarangan

No abstract provided.


Valley Splitting In Si Quantum Dots Embedded In Sige, Srikant Srinivasan Sep 2008

Valley Splitting In Si Quantum Dots Embedded In Sige, Srikant Srinivasan

Srikant Srinivasan

We examine energy spectra of Si quantum dots embedded in Si0.75Ge0.25 buffers using atomistic numerical calculations for dimensions relevant to qubit implementations. The valley degeneracy of the lowest orbital state is lifted and valley splitting fluctuates with monolayer frequency as a function of the dot thickness. For dot thicknesses ≤ 6 nm, valley splitting is found to be >150 μeV. Using the unique advantage of atomistic calculations, we analyze the effect of buffer disorder on valley splitting. Disorder in the buffer leads to the suppression of valley splitting by a factor of 2.5; the splitting fluctuates with ≈ 20 μeV …


Mira V: An Integrated System For Minimally Invasive Robot-Assisted Lung Brachytherapy, A. Trejos, A. Lin, S. Mohan, H. Bassan, C. Edirisinghe, R. Patel, C. Lewis, E. Yu, A. Fenster, R. Malthaner Apr 2008

Mira V: An Integrated System For Minimally Invasive Robot-Assisted Lung Brachytherapy, A. Trejos, A. Lin, S. Mohan, H. Bassan, C. Edirisinghe, R. Patel, C. Lewis, E. Yu, A. Fenster, R. Malthaner

Edward Yu

An integrated system for minimally invasive robot-assisted image-guided lung brachytherapy has been developed. The system incorporates an experimental setup for accurate radioactive seed placement with commercially available dosimetry planning software. The end result is a complete system that allows planning and executing a brachytherapy procedure with increased accuracy. The results of the in vitro seed placement evaluation show that seed misplacement has a significant effect on the volume receiving more than 200% of the dose (V200), and the minimum dosage received by 90% of the volume (D90).


Far-Field Subdiffraction Optical Microscopy Using Metamaterial Crystals: Theory And Simulations, Alessandro Salandrino, Nader Engheta Jan 2008

Far-Field Subdiffraction Optical Microscopy Using Metamaterial Crystals: Theory And Simulations, Alessandro Salandrino, Nader Engheta

Nader Engheta

Here we suggest and explore theoretically an idea for a far-field scanless optical microscopy with a subdiffraction resolution. We exploit the special dispersion characteristics of an anisotropic metamaterial crystal that is obliquely cut at its output plane, or has a curved output surface, in order to map the input field distribution onto the crystal’s output surface with a compressed angular spectrum, resulting in a "magnified" image. This can provide a far-field imaging system with a resolution beyond the diffraction limits while no scanning is needed.


Circuit Elements At Optical Frequencies: Nanoinductors, Nanocapacitors, And Nanoresistors, Nader Engheta, Alessandro Salandrino, Andrea Alù Jan 2008

Circuit Elements At Optical Frequencies: Nanoinductors, Nanocapacitors, And Nanoresistors, Nader Engheta, Alessandro Salandrino, Andrea Alù

Andrea Alù

We present the concept of circuit nanoelements in the optical domain using plasmonic and nonplasmonic nanoparticles. Three basic circuit elements, i.e., nanoinductors, nanocapacitors, and nanoresistors, are discussed in terms of small nanostructures with different material properties. Coupled nanoscale circuits and parallel and series combinations are also envisioned, which may provide road maps for the synthesis of more complex circuits in the IR and visible bands. Ideas for the optical implementation of right-handed and left-handed nanotransmission lines are also forecasted.