Parameterized optical properties of InxAl1-xP alloys.

We report values of parametric-model (PM) parameters that can be used to obtain dielectric functions (refractive indices) from 1.5 to 6.0 eV for ${{\rm In}_x}{{\rm Al}_{1 - x}}{\rm P}$InxAl1-xP alloys of arbitrary compositions $x$x. Using reported pseudo-dielectric data for several In compositions, we extract their dielectric functions by multilayer calculations, then parameterize them with PM lineshapes that well describe the asymmetric nature of their critical point (CP) contributions. We follow the ${E_0}$E0 fundamental bandgap as a function of $x$x, and determine the composition of the indirect-to-direct crossover.

A Parametric Model for Temperature Dependence of Dielectric Function of AlSb Film.

We present analytic representation of dielectric function (ɛ ═ ɛ1 + iɛ2) data from 1.7 to 5.0 eV for the temperature from 300 to 803 K of oxide-free AlSb that are the closest representation to date of the intrinsic bulk dielectric response ɛ of the material. Pseudodielectric functions 'ɛ' were measured on a 1.5 µm thick film grown on (001) GaAs by molecular beam epitaxy. Data were obtained with the film in situ to avoid surface oxidation artifacts. The dielectric function parametric model and multilayer calculation were performed to obtain pure dielectric function and fundamental bandgap (E0) of the AlSb film. The ɛ spectrum was successfully reconstructed by seven polynomials and a pole, which can be used to determine ɛ for arbitrary temperatures. Our results should be useful for device design based on AlSb.

Temperature Dependence of the Dielectric Response and Critical Point Energies of Bi1.85Gd0.15Te3.

The complex dielectric function and band-edge critical point structures of Bi1.85Gd0.15Te3 are reported for temperatures from 28 to 300 K and energies from 0.74 to 6 eV, obtained on bulk Bi1.85Gd0.15Te3 by rotating-compensator spectroscopic ellipsometry. The critical point (CP) energies are determined using numerically calculated second energy derivatives of the data. At low temperature, eight CP structures are identified, while only four CPs are observed at room temperature. As temperature decreases, we also observe blue shifts and significantly enhanced CP structures relative to those obtained at room temperature. The temperature dependence of the CPs are determined by fitting the data to the temperature coefficient and a phenomenological expression that contains the Bose-Einstein statistical factor.

Monitoring of the Binding Between EGFR Protein and EGFR Aptamer Using In-Situ Total Internal Reflection Ellipsometry.

The epidermal growth factor receptor (EGFR) protein has received significant attention in medical biotechnology because it is an important component in cell growth and division. We report the results of a study on the binding between the EGFR protein and the associated aptamer, measured in real time. Aptamers can be used for clinical purposes including macromolecular medicine and basic research. In particular, EGFR aptamers are promising molecular agents for targeting cancer. The data were obtained in-situ with total internal reflection ellipsometry (TIRE), which combines the analytic capability of spectroscopic ellipsometry with the high surface sensitivity of surface plasmon resonance measurements. Our results show that TIRE can be used to determine adsorption of nanoscale biomolecules. Our results are supported by additional data obtained by liquid atomic-force-microscopy.

Parameterization of Dielectric Functions and Phase Transitions of SrTiO3 from 26 to 674 K.

We present parameters that allow the dielectric function (ε = ε1 + iε2) of perovskite SrTiO3 (STO) to be calculated for spectral range from 0.74 to 6.42 eV and temperatures from 26 to 674 K. The ε data of STO were reproduced from a previous report. We use the Tauc-Lorentz model to express ε of STO analytically for each temperature. The ε spectra are successfully parameterized with six Tauc-Lorentz components and a pole. To obtain ε data for arbitrary energies and temperatures over the range given above, we interpolated the parameterized results using cubic polynomials. It is well known that STO has phase transitions near 40 and 105 K, which are reflected well in our modeling. Our data allow complex refractive indices to be calculated at any temperature for device design.

Proposal on the Diagnostic Criteria of Definite Isolated Otolith Dysfunction.

BACKGROUND AND OBJECTIVES: Dizzy patients with abnormal otolith function tests, despite a normal caloric response, are defined as having specific (isolated) otolith organ dysfunction. This study was performed to compare the differences in clinical presentation between isolated otolith dysfunction (iOD) patients with lab- and Sx-based iOD group and lab-based iOD symptoms. SUBJECT AND METHODS: The medical records of 23 iOD patients with normal caloric response but abnormal cervical vestibular evoked myogenic potential (VEMP), ocular VEMP, or subjective visual vertical were reviewed. Non-spinning vertigo was considered as otolith-related symptoms. The patients' age, onset of dizziness, Numeric Rating Scale on the severity of dizziness, and concomitant vestibular disorders were analyzed. RESULTS: Patients in the lab-based iOD group were significantly older than those in the lab- and Sx-based iOD group. Known vestibular disorders were significantly more common in the lab-based iOD group (83.3%) compared to the lab- and Sx-based iOD group (18.2%). Despite the normal caloric response, catch-up saccade was found in the video head impulse test in more than half (54.5%) of the lab-based iOD group patients. There was no catch-up saccade in the lab- and Sx-based iOD group. There were no significant differences in gender ratio, frequency of dizziness attacks, and duration of illness. CONCLUSIONS: We propose new definitions of definite iOD (lab- and Sx-based iOD) and probable iOD (lab- or Sx-based iOD). These new definitions may help researchers to identify patients who are more likely to have true iOD, and facilitate comparisons of results between different studies.

Jugular Bulb Resurfacing With Bone Cement for Patients With High Dehiscent Jugular Bulb and Ipsilateral Pulsatile Tinnitus.

OBJECTIVE: To discuss the possible pathophysiologic mechanism of pulsatile tinnitus (PT) perception due to high jugular bulb with bony dehiscence (HJBD) and its improvement after the dehiscent jugular bulb (JB) resurfacing using bone cement, and to describe the efficacy of an objective measure of PT using transcanal sound recording and spectro-temporal analysis (TSR/STA). STUDY DESIGN: Retrospective case series study. SETTING: A university-based, tertiary care cancer center. PATIENTS: Three PT patients with HJBD. MAIN OUTCOME MEASURE(S): All patients underwent transtympanic resurfacing after the source of PT was confirmed by temporal bone imaging and TSR/STA. Improvement of symptom and the changes in the TSR/STA were analyzed. RESULTS: In the first case, a revision operation was performed due to slightly improved but persistent PT after initial resurfacing with bone pate and a piece of conchal cartilage. Revision transtympanic JB resurfacing was performed in this case using bone cement, and PT resolved immediately after the surgery. In the second and third cases, PT resolved completely, or was much abated, immediately after transtympanic resurfacing with bone cement. The TSR/STA also revealed improvement of PT. The median follow-up duration was 28 months, and all three patients remained asymptomatic or much improved compared with their preoperative status. CONCLUSIONS: Transtympanic resurfacing with bone cement, reinforcing the dehiscent JB to reduce focal turbulent flow, is a simple and effective surgical treatment option in patients with PT due to HJBD. In patients with HJBD, the objective measurement of PT by TSR/STA may be of help in selecting appropriate surgical candidates and objective evaluation of the treatment outcome.

Temperature Dependence of the Dielectric Function of Monolayer MoSe2.

The dielectric function [Formula: see text] of monolayer molybdenum diselenide (MoSe2) is obtained and analyzed at temperatures from 31 to 300 K and at energies from 0.74 to 6.42 eV. The sample is a large-area, partially discontinuous monolayer (submonolayer) film of MoSe2 grown on a sapphire substrate by selenization of pulsed laser deposited MoO3 film. Morphological and optical characterizations verified the excellent quality of the film. The MoSe2 data were analyzed using the effective medium approximation, which treats the film and bare substrate regions as a single layer. Second derivatives of ε with respect to energy were numerically calculated and analyzed with standard lineshapes to extract accurate critical-point (CP) energies. We find only 6 CPs for monolayer MoSe2 at room temperature. At cryogenic temperatures 6 additional structures are resolved. The separations in the B- and C-excitonic peaks are also observed. All structures blue-shift and sharpen with decreasing temperature as a result of the reducing lattice constant and electron-phonon interactions. The temperature dependences of the CP energies were determined by fitting the data to the phenomenological expression that contains the Bose-Einstein statistical factor and the temperature coefficient.

Multifunctional Bilayer Template for Near-Infrared-Sensitive Organic Solar Cells.

For organic solar cells (OSCs) based on nonplanar phthalocyanines, it has previously been reported that a thin film composed of triclinic crystals with face-on (or flat-lying)-oriented molecules, typically obtained with a CuI template layer, is desired for optical absorption in the near-infrared (NIR) spectral region. However, this work demonstrates that for a PbPc-C60 donor-acceptor pair, less face-on orientation with a broader orientation distribution obtained with a new template layer consisting of a ZnPc/CuI bilayer is more desirable in terms of solar cell efficiency than the face-on orientation. A NIR-sensitive PbPc-C60 OSC employing this bilayer-templated PbPc film is found to increase the internal quantum efficiency (IQE) by 36% on average in the NIR spectral region compared to a device using a CuI-templated PbPc film. Analyses of the change in IQE using the exciton diffusion model and the entropy- and disorder-driven charge-separation model suggest that the improved IQE is attributed to the facilitated dissociation of charge-transfer excitons as well as the reduction in exciton quenching near the indium tin oxide surface.

Dielectric functions of solution-processed GdAlO(x)/Si films measured with vacuum ultra-violet spectroscopic ellipsometry.

The dielectric functions of amorphous GdAlO(x) (GAO) films grown by the sol-gel process were investigated from 1.12 to 8.5 eV as a function of annealing temperature using spectroscopic ellipsometry (SE). A GAO precursor sol with a molar ratio of Gd:Al = 1:1 was prepared. Thin layers were formed by spin-coating on p-type Si substrates. The layers were sintered at 400 degrees C for 2 h in an ambient atmosphere, then rapid-thermal-annealed (RTA) at 700 or 800 degrees C for 1 min in an N2 ambient. The optical properties were measured via variable angle SE, at room temperature. The angle of incidence was varied from 50 to 70 degrees in 10 degrees steps. The dielectric functions of the resulting GAO films were obtained from the measured pseudodielectric functions by multilayer-structure calculations using the Tauc-Lorentz (TL) dispersion relation. The real and imaginary parts of the dielectric functions were found to increase with increasing RTA temperature. The film thicknesses and TL parameters (threshold energy E(g) and broadening C) decrease with increasing RTA temperature.