How Pop-Culture Shaped Momiji Inubashiri

This presentation will talk about the effect of memes on the character Momiji Inubashiri. Momiji is a character from the video game Touhou 10: Mountain of Faith. She\u27s the stage 4 mid boss and has minimal dialog throughout the series. The character has been mostly given life through memes. I thought that was absolutely fascinating, so I did a deep dive on the subject.https://digitalcommons.usu.edu/fsrs2020/1080/thumbnail.jp

Magnetic Response Versus Lift Height of Thin Ferromagnetic Films

The interaction between a magnetic force microscope (MFM) tip and ferromagnetic films of Ni, Co90Fe10 and Py with in-plane magnetization has been investigated. The measured interaction, due to the magnetizing of the films by the MFM tip field, was determined by the phase shift of the cantilever response. The tip-film separation or lift height dependent phase shift was found to be independent of the saturation magnetization of the ferromagnetic film. The result is identical for all three films and micromagnetic simulations give similar results. The reason is at a given tip-sample separation the tip induced magnetization of the film creates a demagnetization field which is equal in magnitude to the tip field at that separation

Hybrid functional study of nonlinear elasticity and internal strain in zinc-blende III-V materials

We investigate the elastic properties of selected zinc-blende III-V semiconductors. Using hybrid functional density functional theory, we calculate the second- and third-order elastic constants and first- and second-order internal strain tensor components for Ga, In, and Al containing III-V compounds. For many of these parameters, there are no available experimental measurements, and this work is the first to predict their values. The stricter convergence criteria for the calculation of higher-order elastic constants are demonstrated, and arguments are made based on this for extracting these constants via the calculated stresses, rather than the energies, in the context of plane-wave-based calculations. The calculated elastic properties are used to determine the strain regime at which higher-order elasticity becomes important by comparing the stresses predicted by a lower- and a higher-order elasticity theory. Finally, the results are compared with available experimental literature data and previous theory

Electronic and excitonic properties of ultrathin (In,Ga)N layers: the role of alloy and monolayer width fluctuations

We present an atomistic theoretical analysis of the electronic and excitonic properties of ultrathin, monolayer thick wurtzite (In,Ga)N embedded in GaN. Our microscopic investigation reveals that (i) alloy fluctuations within the monolayer lead to carrier localization effects that dominate the electronic and optical properties of these ultrathin systems and that (ii) excitonic binding energies in these structures exceed the thermal energy at room temperature, enabling excitonic effects to persist even at elevated temperatures. Our theoretical findings are consistent with, and provide an explanation for, literature experimental observations of (i) broad photoluminescence linewidth and (ii) excitonic effects contributing to the radiative recombination process at elevated temperatures. When accounting for small structural inhomogeneities, such as local thickness fluctuations of one monolayer, "indirect" excitons may be found, with electrons and holes independently localized in different spatial positions. This result also provides further arguments for experimentally observed effects such as (i) non-exponential decay curves in time dependent photoluminescence spectra and (ii) the "S"-shape temperature dependence of the photoluminescence peak energies. Overall, our results provide fundamental understanding, on an atomistic level, of the electronic and optical properties of ultrathin, quasi 2D (In,Ga)N monolayers embedded in GaN, and offer guidance for the tailoring of their properties for potential future device applications

Atomistic analysis of piezoelectric potential fluctuations in zinc-blende InGaN/GaN quantum wells: A Stillinger-Weber potential based analysis

In this paper we investigate strain and local polarization field effects in zinc-blende indium gallium nitride (InGaN) alloys and quantum wells. To do so we parametrize and establish a Stillinger-Weber potential with parameters fitted to hybrid functional density functional theory data. The developed model gives very good agreement with quantities to which it has not been fitted, such as Kleinman parameters of cubic III-N materials or the composition dependence of the lattice constant in InGaN alloys. Equipped with this model, we extract the composition dependence of elastic constants C11 and C12 in InGaN alloys, including bowing parameters for these quantities, which may form input for continuum-based calculations. Furthermore, applying this model to InGaN alloys and wells reveals that random alloy fluctuations can lead to strong local strain field fluctuations. Building on this information, we present a model that allows for the calculation of connected local built-in field fluctuations at the microscopic level, accounting for first- and second-order piezoelectric effects. The approach is general and can be applied to any zinc-blende III–V alloy or heterostructure investigated in the frame of semiempirical models (e.g., valence force field models) targeting strain fields on an atomistic level. Here, building on our Stillinger-Weber potential we show that local strain fluctuations in zinc-blende InGaN quantum wells can lead to strong piezoelectric built-in field fluctuations. This contribution has been widely overlooked in previous theoretical studies of these systems. Finally, we briefly discuss the impact of these polarization field fluctuations on carrier localization effects in such quantum well systems

Interface roughness, carrier localization, and wave function overlap in c-Plane (In,Ga)N/GaN quantum wells: interplay of well width, alloy microstructure, structural inhomogeneities, and Coulomb effects

In this work, we present a detailed analysis of the interplay of Coulomb effects and different mechanisms that can lead to carrier-localization effects in c-plane (In,Ga)N/GaN quantum wells. As mechanisms for carrier localization, we consider here effects introduced by random alloy fluctuations as well as structural inhomogeneities such as well-width fluctuations. Special attention is paid to the impact of the well width on the results. All calculations have been carried out in the framework of atomistic tight-binding theory. Our theoretical investigations show that independent of the well widths studied here, carrier-localization effects due to built-in fields, well-width fluctuations, and random-alloy fluctuations dominate over Coulomb effects in terms of charge-density redistributions. However, the situation is less clear cut when the well-width fluctuations are absent. For a large well width (approximately >2.5nm), charge-density redistributions are possible, but the electronic and optical properties are basically dominated by the out-of-plane carrier separation originating from the electrostatic built-in field. The situation changes for lower well widths (<2.5nm), where the Coulomb effect can lead to significant charge-density redistributions and, thus, might compensate for a large fraction of the spatial in-plane wave-function separation observed in a single-particle picture. Given that this in-plane separation has been regarded as one of the main drivers behind the green gap problem, our calculations indicate that radiative recombination rates might significantly benefit from a reduced quantum-well-barrier-interface roughness

Positive plant-soil feedbacks of the invasive <i>Impatiens glandulifera</i> and their effects on above-ground microbial communities

Impatiens glanduliferais one of the most widespread invasive plant species in the UK. Although aspects of its biology are known, there is little information about its association with microbial communities, both above ground and below ground. Furthermore, it is unknown whether this species exhibits any form of plant&ndash;soil feedback (PSF), commonly seen in other invasive weeds. We conducted a PSF experiment, in which plants ofI.glanduliferawere grown in soil that supported the species and compared with plants grown in a control soil from the same locality. Soil nutrients were measured, and the soil and foliar microbial communities were assessed.Impatiens glanduliferagrew larger and faster in conditioned soil compared with the control. Higher levels of phosphate were also found in conditioned soils. Arbuscular mycorrhizal fungal (AMF) colonisation was lower in conditioned soils, suggesting thatI.glanduliferamay rapidly alter AMF communities in invaded areas. PSFs had a significant effect on the foliar endophyte community, with clear separation of species between conditioned and control soils. These results show thatI.glanduliferadisplayed a positive PSF and the PSF mechanism extended beyond the soil microbial community to affect foliar endophytes. The observed increase in endophytes in plants grown in conditioned soil could enhance resistance to herbivory, thus further accentuating the invasive properties of this species