Download or read book Near field Optical Microscope Investigations of Inmmiscibility Effects and Photoreflectance Contrast in III V Semiconductor Materials written by Charles A. Paulson and published by . This book was released on 2002 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spatial Temporal Resolution in Near Field Optical Microscopy written by Hans Hallen and published by . This book was released on 1998 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project elucidated and examined the unique science behind the spectral and temporal contrast of near field scanning optical microscopy, illuminated the technology this enabled, and considered the limits of simultaneous position, time and spectral resolution. Specifically, (1) High-resolution, quantitative measurements of excess carrier lifetime in silicon were acquired in a novel, all-optical technique. The contrast in the images was modeled and is of interest since the resolution is significantly shorter than the carrier diffusion length. (2) a Ti-sapphire laser has been constructed and modified to decrease pump power requirements so that measurements can be made before the carriers diffuse from under the probe. Novel electron-hole droplet effects are expected. (3) Spectroscopic nano-Raman images were acquired for the first time. The Raman data illustrated interesting manifestations of a near-field in comparisons with far-field spectroscopy. (4) The first and most thorough studies of the optical and thermal properties of near-field scanning optical microscope probes gave insights which led to the development of a new generation of high throughput probes. Other results reflect instrumentation advances: (5) A new constant linear motion system useful for NSOM or other probe microscope coarse approach. (6) A new, low cost force feedback system. (7) A nanometer-resolution, kHz bandwidth, millimeter range position sensor.

Download or read book Near field Scanning Optical Microscopy Studies of Electronic and Photonic Materials and Devices written by Julia W. P. Hsu and published by . This book was released on 2001 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Near field Scanning Optical Microscopy Studies of Electronic and Photonic Materials and Devices written by Julia W. P. Hsu and published by . This book was released on 2001 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Near field Scanning Optical Microscopy of Soft Organic Materials written by Lynn Fong Lee and published by . This book was released on 2005 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Near field Scanning Optical Microscopy Studies of Electronic and Photonic Materials and Devices written by J. W. Hsu and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Contrast and Resolution Enhancement in Near field Optical Microscope by Using a Modulation Technique written by Eldad Palachi and published by . This book was released on 1999 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Near field Scanning Optical Microscopy of Semiconductor Lasers and Materials written by William D. Herzog and published by . This book was released on 2000 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Application of Near Field Optics to Semiconductor Materials Characterization written by and published by . This book was released on 1999 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: This grant supported a program for local spectroscopic studies of semiconductor nanostructure materials. Our work has looked at the various types of techniques of near field optics and pursued the options that are optimized for the optical spectroscopy of semiconductor nanostructures. The thrust of the research has involved the use of solid immersion lenses. This form of near field optics strikes a balance between the need for high spatial resolution and high optical throughput. We have demonstrated that these techniques can be implemented within the context of a cryogenic system and obtain spatial resolution of order lambda3. We have used these techniques to characterize naturally occurring quantum dots in thin GaAs quantum wells. Our studies reveal the surprising fact that these samples have not only zero dimensional excitons but also two dimensional excitons. In fact, most of the material plays host to the two dimensional species while the zero dimensional species occupies only 1-3% of the sample. This result is surprising because all of the light emission comes from the zero dimensional exciton. The two dimensional exciton is observed using photoluminescence excitation diffusion, a technique wherein we are able to generate a local optical excitation and watch it diffuse.

Download or read book Investigation of the Optical Properties of Ordered Semiconductor Materials written by Jack McCrae and published by . This book was released on 1997-01-01 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical Studies have been conducted upon CdGeAs2 and ZnGeP2, two of the most promising semiconductors being developed for mid-infrared non-linear optics applications. These experiments included photoluminescence (PL) studies of both compounds as well as photoreflectance (PR) measurements upon CdGeAs2. In addition, Hall effect measurements were carried out upon CdGeAs2, to aid in interpretation of the optical data. PL was measured as a function of laser power, sample temperature, and crystal orientation for CdGeAs2. One broad weak peak near 0.38 eV, and another somewhat narrower and often far brighter peak near 0.57 eV were found by low temperature (4 K) PL measurements. Strongly polarized PL was observed with the E field of the PL parallel to the material's c-axis. A polarization ratio as high as 6:1 was observed. PL on ZnGeP2 in the mid-IR revealed a previously unreported PL peak near 0.35 eV. PR measurements on CdGeAs2 allowed the estimation of the bandgap as a function of temperature. Hall effect measurements on CdGeAs2 reveals the dominant acceptor level lies about 120 meV above the valence band.

Download or read book Optical Properties of III V Semiconductors written by Heinz Kalt and published by Springer. This book was released on 2012-10-23 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph is concerned with the III-V bulk and low-dimensional semiconductors, with the emphasis on the implications of multi-valley bandstructures for the physical mechanisms essential for opto-electronic devices. The optical response of such semiconductor materials is determined by many-body effects such as screening, gap narrowing, Fermi-edge singularity, electron-hole plasma and liquid formation. Consequently, the discussion of these features reflects such interdependencies with the dynamics of excitons and carriers resulting from intervalley coupling.

Download or read book Electrical and Optical Studies of III V Semiconductor Devices and Materials written by Christopher Amos Payling and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Near Field Scanning Optical Microscopy of Polycrystalline Semiconductors written by Mary Kay Herndon and published by . This book was released on 1999 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Near field Scanning Optical Microscopy Studies of Photnonic Structures and Materials written by Anthony Louis Campillo and published by . This book was released on with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigations and Developments Towards a Calibration Standard for Scanning Near Field Optical Microscopy written by Matthias Marcus Wellhöfer and published by . This book was released on 2002 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Exploring Optical Nonlinearities in III V Semiconductors written by Mfon Odungide and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This Master's dissertation focuses on exploring optical nonlinearities in IIIV semiconductors. This work covers a range of III-V materials and a few devices. To begin with, optical characterization of Aluminium Gallium Arsenide (AlGaAs) waveguides with enhanced nonlinear optical interactions was carried out. We have experimentally demonstrated wide conversion ranges andhigh conversion efficiencies for four-wavemixing inAlGaAswaveguides with three different geometries. In addition to that, both linear and nonlinear losses in each of these geometries were explored. AlGaAs represents only one compound of the large group of III-V semiconductors. To explore the potentials of other semiconductors compounds of this group for nonlinear optics, it is imperative to have information about refractive indices of different III-V compounds. This refractive index information is only available for some binary compounds in isolated spectral windows. In this thesis, we developed a model capable of predicting the values of the refractive indices of binary, ternary and quaternary III-V semiconductor compounds from the values of their band-gap energies. We compared the value predicted by our proposed model with existing experimental data and it was found not only is the predicted values in good agreement with the known values, but also has a lower error margin when compared to previously reported models. Finally, in quest for more suitable material platform for nonlinear photonic integration at different wavelength ranges, a detailed analysis of other potential III-V compounds not previously explored for photonic integration is presented.

Download or read book Optical Properties of III V Semiconductor Nanostructure and Quantum Wells written by and published by . This book was released on 2002 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors have investigated the interband and intersubband transitions in III-V semiconductor quantum wells and quantum dots. They also investigated intersubband transitions in III-nitride multiple quantum wells grown on a sapphire substrate, in particular, intersubband transitions in InGaAs/GaAs multiple quantum dots and GaN/AlGaN multiple quantum wells. Polarization effect on the phonon modes in GaN/AlGaN heterojunctions field effect transistors also were reported. The report contains detailed discussions of the results obtained during the last 18 months. It concludes with a list of related technical papers, books, and symposia. (1 table, 10 figures, 63 refs.).