Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- AFM (1)
- Anisotropic aerogel (1)
- Atomic force microscope (1)
- Electric field. (1)
- Electromagnetic wave (1)
-
- Finite-difference time-domain (1)
- Force distance spectroscopy (1)
- GaN (1)
- Gold (1)
- Meep (1)
- Nanorods (1)
- Nickel (1)
- Photo-crosslinking (1)
- Photolithography (1)
- Photoluminescence (1)
- Photoluminescence GaN (1)
- Plasmons (1)
- Silver (1)
- Silver Nanoparticle Catalyst (1)
- Sol-gel (1)
- Surface plasmons (1)
- Young's modulus (1)
Articles 1 - 6 of 6
Full-Text Articles in Physics
Photoluminescence From Bulk Gan Substrates, Marrwa Alrrshedan
Photoluminescence From Bulk Gan Substrates, Marrwa Alrrshedan
Theses and Dissertations
Photoluminescence (PL) has been studied from different types of bulk GaN samples grown by hydride vapor phase epitaxy technique at Kyma Technologies. Point defects in bulk and at the surface affect the electrical and optical properties of GaN and could be analyzed by PL. The surface of the samples was polished with different techniques: one is chemical mechanical polish (CMP) and another is mechanical polish (MP). PL data from MP and CMP surfaces show that PL intensity from the CMP-treated surface is much higher than that from the MP-treated surface. This can be explained by defects formed during the process …
Preferentially Orienting Ag Nanoparticles Using Caf2 Nanorods, Mathias Auer
Preferentially Orienting Ag Nanoparticles Using Caf2 Nanorods, Mathias Auer
Theses and Dissertations
A study was done to examine the effect of surface orientation as well as heterogeneous epitaxy at an interface between two materials with a large lattice mismatch. Silver nanoparticles of different diameters were grown in an effort to study methods of preferentially orienting the geometry of metal nanoparticles. Arrays of calcium fluoride nanorods were grown on silicon substrates using oblique angle thermal vapor deposition. The chamber operated at an ultra high vacuum pressure of 10^-10 Torr during the deposition of the rods and an oblique angle of 75° was kept between the silicon substrate normal and the direction of incident …
Finite-Difference Time-Domain Modeling Of Nickel Nanorods, Joseph Steele Parris
Finite-Difference Time-Domain Modeling Of Nickel Nanorods, Joseph Steele Parris
Theses and Dissertations
Theoretical and experimental plasmonics is a growing field as a method to create near fields at sub-wavelength distances. In this thesis, a finite-difference time-domain method is used to simulate electromagnetic waves onto a thin film that present of nickel nanorods with sharp apexes. The absorbed, transmitted, and reflected fields were shown to depend linearly on silver film thickness and nanotip length. The electric field is visualized along the tip to show strong charge density along the base of the tip’s apex and how that density changes for wavelength, metal, and source tilt. Lastly, the study shows gold film on the …
Mechanical Characterization Of Patterned Silver Columnar Nanorods With The Atomic Force Microscope., Sean Kenny
Mechanical Characterization Of Patterned Silver Columnar Nanorods With The Atomic Force Microscope., Sean Kenny
Theses and Dissertations
Patterned silver (Ag) columnar nanorods were prepared by the glancing angle physical vapor deposition method. The Ag columnar nanorods were grown on a Si (100) substrate patterned with posts in a square “lattice” of length 1 μm. An electron beam source was used as the evaporation method, creating the deposition flux which was oriented 85˚ from the substrate normal. A Dimension Icon with NanoScope V controller atomic force microscope was used to measure the spring constant in 10 nm increments along the long axis of five 670 nm long Ag nanorod specimens. The simple beam bending model was used to …
Fabrication Of Anisotropic Sol-Gel Materials By Photo-Crosslinking, Charles Wingfield
Fabrication Of Anisotropic Sol-Gel Materials By Photo-Crosslinking, Charles Wingfield
Theses and Dissertations
This is a report on the fabrication and characterization of anisotropic, porous materials: functionally graded cellular and compositionally anisotropic aerogels. This new class of materials was fabricated by photopolymerization of selected regions of a homogeneous monolith using visible light. Visible light is not significantly absorbed and not significantly scattered by organic molecules and oxide nanoparticles in wet gels and it allows fabrication of deeply penetrating, well-resolved patterns. Simple variations of the exposure geometry allowed fabrication of a wide variety of anisotropic materials without requiring layers or bonding.
Thermal Quenching Of Photoluminescence From Gan, Anita Olsen
Thermal Quenching Of Photoluminescence From Gan, Anita Olsen
Theses and Dissertations
GaN is a III-V semiconductor that is a promising material used in production of light emitting devices and high power/high frequency electronics. The electronic and optical properties of GaN are subdued by defects that occur during the growth processes of this material. The emitted photoluminescence (PL) from optically excited GaN gives insight into the origins and effects of point defects within the crystal lattice structure of GaN. In this study, PL spectroscopy is used to examine and analyze the point defects that occur in Zn-doped GaN. The blue luminescence band seen in undoped and Zn-doped GaN have identical fine structure …