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Full-Text Articles in Physics

Isolation Enhancement For Cylindrical Structure Millimeter-Wave Repeaters, Brad Frank Allen Apr 2018

Isolation Enhancement For Cylindrical Structure Millimeter-Wave Repeaters, Brad Frank Allen

Electrical, Computer & Energy Engineering Graduate Theses & Dissertations

In radio frequency (RF), microwave, and millimeter wave (mmw) repeater applications, the receiver (RX) often needs to detect small power levels while simultaneously transmitting (TX) the same signal amplified significantly without distorting the incoming signal. In some applications, this can be done with time division or frequency division duplexing techniques; however, there are full duplex repeater applications that require simultaneous transmit and receive at the same time and same frequency. These full duplex systems often face the challenge of self-interference caused by the transmitter (TX to RX isolation).

This thesis focuses on enhancing the isolation between two antennas on a ...


Scalable Quantum Light Sources In Silicon Photonic Circuits, Cale Michael Gentry Apr 2018

Scalable Quantum Light Sources In Silicon Photonic Circuits, Cale Michael Gentry

Electrical, Computer & Energy Engineering Graduate Theses & Dissertations

Chip-scale integrated photonic circuits provide an attractive platform for the implementation of many quantum photonic technologies ranging from precise metrology to secure communication and quantum computation. In particular, silicon photonic platforms support micron-scale nonlinear optical sources of non-classical light which can be mass manufactured using the robust fabrication processes pioneered by the CMOS microelectronics industry. Integration of these quantum photonic sources with high-performance classical photonic devices on the same chip is required for truly scalable quantum information technologies. Integrated nonlinear resonators are investigated as sources of quantum mechanically correlated photon pair sources. An all-order dispersion engineering method is presented as ...


Application Of Plasmonics In Energy Harvesting, Dawei Lu Apr 2015

Application Of Plasmonics In Energy Harvesting, Dawei Lu

Electrical, Computer & Energy Engineering Graduate Theses & Dissertations

This thesis studies the application of plasmonics in solar energy conversion and near field thermal energy harvesting.

The efficiency of semiconductor solar cell is limited by the inability of absorbing photons with energy below the bandgap. By designing plasmonic nanograting with resonance at the absorption edge, ~10% overall absorption improvement is achieved. Both localized and propagating surface plasmon modes are observed in the device. Their interaction, and the influence on overall solar cell absorption performance are studied in details.

In addition, this thesis studies the upconversion materials which can convert unabsorbed near infrared photons by semiconductor solar cells into well ...


Localization Of Dense Clusters Of Nanoscale Emitters For Super-Resolution Microscopy, Anthony J. Barsic Apr 2014

Localization Of Dense Clusters Of Nanoscale Emitters For Super-Resolution Microscopy, Anthony J. Barsic

Electrical, Computer & Energy Engineering Graduate Theses & Dissertations

Single-Molecule Localization Microscopy is an optical imaging paradigm which provides computational reconstructions of microscopic objects much smaller than the imaging wavelength. Information regarding physical dimensions of small structures arises from precise localization of individual fluorophores attached to targets within the sample. Complete reconstructions require precise localizations for which neighboring emitters must be resolved beforehand. Control of experimental conditions ensures adjacent emitters are not likely to be activated in the same camera frame. As a result, the gain in spatial resolution occurs at the expense of the acquisition time. Unfortunately, this approach necessitates many images to generate a well-sampled reconstruction. The ...


Engineering Optical Properties Using Plasmonic Nanostructures, Venkata Ananth Tamma Apr 2012

Engineering Optical Properties Using Plasmonic Nanostructures, Venkata Ananth Tamma

Electrical, Computer & Energy Engineering Graduate Theses & Dissertations

Plasmonic nanostructures can be engineered to take on unusual optical properties not found in natural materials. The optical responses of plasmonic materials are functions of the structural parameters and symmetry of the nanostructures, material parameters of the nanostructure and its surroundings and the incidence angle, frequency and polarization state of light. The scattering and hence the visibility of an object could be reduced by coating it with a plasmonic material. In this thesis, presented is an optical frequency scattering cancelation device composed of a silicon nanorod coated by a plasmonic gold nanostructure. The principle of operation was theoretically analyzed using ...