The Roles of a Consultant in a Cooperative System Headquarters

published or submitted for publicatio

Band engineering in dilute nitride and bismide semiconductor lasers

Highly mismatched semiconductor alloys such as GaNAs and GaBiAs have several novel electronic properties, including a rapid reduction in energy gap with increasing x and also, for GaBiAs, a strong increase in spin orbit- splitting energy with increasing Bi composition. We review here the electronic structure of such alloys and their consequences for ideal lasers. We then describe the substantial progress made in the demonstration of actual GaInNAs telecomm lasers. These have characteristics comparable to conventional InP-based devices. This includes a strong Auger contribution to the threshold current. We show, however, that the large spin-orbit-splitting energy in GaBiAs and GaBiNAs could lead to the suppression of the dominant Auger recombination loss mechanism, finally opening the route to efficient temperature-stable telecomm and longer wavelength lasers with significantly reduced power consumption.Comment: 27 pages, 11 figure

Waiting to exhale: Somatic responses to place and the genocidal sublime

This paper examines various theories of trauma and representation to critically reflect upon the production of a digital diptych installation designed to reward stillness and contemplation. The exegesis considers various artistic strategies including eye-witness testimony, silence, place, ethnographic documentary and poeisis

Theory and design of Inx_{x}Ga1−x_{1-x}As1−y_{1-y}Biy_{y} mid-infrared semiconductor lasers: type-I quantum wells for emission beyond 3 μ\mum on InP substrates

We present a theoretical analysis and optimisation of the properties and performance of mid-infrared semiconductor lasers based on the dilute bismide alloy In$_{x}$Ga$_{1-x}$As$_{1-y}$Bi$_{y}$, grown on conventional (001) InP substrates. The ability to independently vary the epitaxial strain and emission wavelength in this quaternary alloy provides significant scope for band structure engineering. Our calculations demonstrate that structures based on compressively strained In$_{x}$Ga$_{1-x}$As$_{1-y}$Bi$_{y}$ quantum wells (QWs) can readily achieve emission wavelengths in the 3 -- 5 $\mu$m range, and that these QWs have large type-I band offsets. As such, these structures have the potential to overcome a number of limitations commonly associated with this application-rich but technologically challenging wavelength range. By considering structures having (i) fixed QW thickness and variable strain, and (ii) fixed strain and variable QW thickness, we quantify key trends in the properties and performance as functions of the alloy composition, structural properties, and emission wavelength, and on this basis identify routes towards the realisation of optimised devices for practical applications. Our analysis suggests that simple laser structures -- incorporating In$_{x}$Ga$_{1-x}$As$_{1-y}$Bi$_{y}$ QWs and unstrained ternary In$_{0.53}$Ga$_{0.47}$As barriers -- which are compatible with established epitaxial growth, provide a route to realising InP-based mid-infrared diode lasers.Comment: Submitted versio

Areal Geology of the Post-Paleozoic Surface of the Northwest Plains

Probably most of the area included in this report has been ex­amined to some extent by oil geologists, and most, if not all, of the important domes have been discovered and surveyed thoroughly. In parts of the area, the bedrock is covered by glacial drift or alluvium materi­al, but it is reasonable to believe that no new domal structure will be found. This means that surface examination alone will be insufficient in locating new oil fields, so future prospecting will be dependent, to a great extent, on studies of sub-surface stratigraphy

Warner Bros. v. Nelson: A Prelude to the De Havilland Law

In 1944, the California Court of Appeals handed down its landmark decision in De Haviland v. Warner Bros ending the practice of studios extending personal service contracts beyond the statutory limit of seven years by adding suspension periods incurred during the contract term. “Suspension/extension” could double the term of an actor’s contract. The De Haviland case has justly received much attention, but an earlier case, Warner Bros. v. Nelson, in which Bette Davis also challenged the practice of suspension/extension, merits more attention than it has received. In Warner Bros. Nelson, Davis argued that her studio contract should not be enforced on several grounds including that the suspension/extension clauses were inequitable. During the trial, the studio waived its powerful rights to suspension/extension for reasons previously unknown. Not until now has that waiver been properly contextualized with the help of archival research of studio records. Furthermore, archival research has uncovered that the studio explored revising and limiting its power of suspension/extension as a result of Davis’s arguments. This Article reveals that Davis achieved much more than was previously understood. It discusses how these cases, in particular De Haviland, still resonate today in the sports and entertainment industries. It also suggests that the recent dispute between the Writers Guild of America and the Association of Talent Agents can be viewed as a consequence of these cases

From Theory to Practice: Creating a Toolkit for Engaged Design

Researchers and designers alike have called for more inclusive and participatory approaches to be used within design. By first exploring the work of researchers designing with older adults living with dementia and expanding to a more robust literature review surrounding inclusion in design, I found that the literature not only suggests that design could benefit from an integration of interdisciplinary knowledge, critical reflection of methods and intentional interaction with users, but also presents theories for doing so. This project condenses four of those theories into key principles, and uses them to present a framework of Engaged Design, a mindset intended to helps designers prioritize critical reflection of their processes in order to interact more meaningfully with their users.Master of ScienceInformation, School ofUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/162557/1/Broderick_Brianna_Final_MTOP_Thesis_20200501.pd

Effects of Strong Magnetic Fields in Strange Baryonic Matter

We investigate the effects of very strong magnetic fields upon the equation of state of dense bayonic matter in which hyperons are present. In the presence of a magnetic field, the equation of state above nuclear density is significantly affected both by Landau quantization and magnetic moment interactions, but only for field strengths $B>5\times10^{18}$ G. The former tends to soften the EOS and increase proton and lepton abundances, while the latter produces an overall stiffening of the EOS. Each results in a supression of hyperons relative to the field-free case. The structure of a neutron star is, however, primarily determined by the magnetic field stress. We utilize existing general relativistic magneto-hydrostatic calculations to demonstrate that maximum average fields within a stable neutron are limited to values $B\le 1-3 \times10^{18}$ G. This is not large enough to significantly influence particle compositions or the matter pressure, unless fluctuations dominate the average field strengths in the interior or configurations with significantly larger field gradients are considered.Comment: 12 pages, 3 figures. To be submitted to Phys. Lett.