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Using ab initio density functional total energy and molecular dynamics simulations, we study the effects of various forms of nitrogen post deposition anneal (PDA) on the electric properties of hafnia in the context of its application as a gate dielectric in field effect transistors (FET). We consider the atomic structure and energetics of nitrogen containing defects which can be formed during the PDA in various N-based ambients: N2, N+2, N, NH3, NO, N2O. We analyse the role of such defects in fixed charge accumulation, electron trapping and in the growth of the interface SiOx layer. We find that nitrogen anneal of the oxides leads to an effective immobilization of native defects such as oxygen vacancies and interstitial oxygen ions, which may inhibit growth of silica layer. Nitrogen in any form effectively incorporates into the pre-existing oxygen vacancies and, therefore may decrease the concentration of shallow electron traps. However, nitrogen in any form is unlikely to significantly reduce the fixed charge in the dielectric.

The combination of density functional theory and single-site dynamical mean-field theory, using both Hartree and full continuous-time quantum Monte Carlo impurity solvers, is used to study the metal-insulator phase diagram of perovskite transition-metal oxides of the form $AB$O$_3$ with a rare-earth ion $A$=Sr, La, Y and transition metal $B$=Ti, V, Cr. The correlated subspace is constructed from atomiclike $d$ orbitals defined using maximally localized Wannier functions derived from the full $p$-$d$ manifold; for comparison, results obtained using a projector method are also given. Paramagnetic DFT+DMFT computations using full charge self-consistency along with the standard "fully localized limit" (FLL) double counting are shown to incorrectly predict that LaTiO$_3$, YTiO$_3$, LaVO$_3$ and SrMnO$_3$ are metals. A more general examination of the dependence of physical properties on the mean $p$-$d$ energy splitting, the occupancy of the correlated $d$ states, the double-counting correction, and the lattice structure demonstrates the importance of charge-transfer physics even in the early transition-metal oxides and elucidates the factors underlying the failure of the standard approximations. If the double counting is chosen to produce a $p$-$d$ splitting consistent with experimental spectra, single-site dynamical mean-field theory provides a reasonable account of the materials properties. The relation of the results to those obtained from "$d$-only" models in which the correlation problem is based on the frontier orbital $p$-$d$ antibonding bands is determined. It is found that if an effective interaction $U$ is properly chosen the $d$-only model provides a good account of the physics of the $d^1$ and $d^2$ materials.

Vanadium dioxide (VO2) undergoes a sharp metal-insulator transition (MIT) in the vicinity of room temperature and there is great interest in exploiting this effect in novel electronic and photonic devices. We have measured the work function of VO2 thin films across the phase transition for the first time using variable temperature Kelvin force microscopy (KFM). The work function of VO2 is estimated to be 5.15 eV in the insulating phase and increases by approximately 0.15 eV across the MIT. We further show that the work function change upon the phase transition is highly sensitive to near-surface stoichiometry studied by X-ray photoelectron spectroscopy. The results are pertinent to understanding fundamental electronic properties of vanadium oxide as well as charge injection phenomena in solid state devices incorporating complex oxides containing multi-valent cations.

We report a comprehensive first-principles study of the thermodynamics and transport of intrinsic point defects in layered oxide cathode materials LiMO$_2$ (M=Co, Ni), using density-functional theory and the Heyd-Scuseria-Ernzerhof screened hybrid functional. We find that LiCoO$_2$ has a complex defect chemistry; different electronic and ionic defects can exist under different synthesis conditions, and LiCoO$_2$ samples free of cobalt antisite defects can be made under Li-excess (Co-deficient) environments. A defect model for lithium over-stoichiometric LiCoO$_2$ is also proposed, which involves negatively charged lithium antisites and positively charged small (hole) polarons. In LiNiO$_2$, a certain amount of Ni$^{3+}$ ions undergo charge disproportionation and the concentration of nickel ions in the lithium layers is high. Tuning the synthesis conditions may reduce the nickel antisites but would not remove the charge disproportionation. In addition, we find that LiMO$_2$ cannot be doped $n$- or $p$-type; the electronic conduction occurs via hopping of small polarons and the ionic conduction occurs via migration of lithium vacancies, either through a monovacancy or divacancy mechanism, depending on the vacancy concentration.

Using a linear combination of atomic orbitals approach, we report a systematic comparison of various Density Functional Theory (DFT) and hybrid exchange-correlation functionals for the prediction of the electronic and structural properties of prototypical ferroelectric oxides. It is found that none of the available functionals is able to provide, at the same time, accurate electronic and structural properties of the cubic and tetragonal phases of BaTiO$_3$ and PbTiO$_3$. Some, although not all, usual DFT functionals predict the structure with acceptable accuracy, but always underestimate the electronic band gaps. Conversely, common hybrid functionals yield an improved description of the band gaps, but overestimate the volume and atomic distortions associated to ferroelectricity, giving rise to an unacceptably large $c/a$ ratio for the tetragonal phases of both compounds. This super-tetragonality is found to be induced mainly by the exchange energy corresponding to the Generalized Gradient Approximation (GGA) and, to a lesser extent, by the exact exchange term of the hybrid functional. We thus propose an alternative functional that mixes exact exchange with the recently proposed GGA of Wu and Cohen [Phys. Rev. B 73, 235116 (2006)] which, for solids, improves over the treatment of exchange of the most usual GGA's. The new functional renders an accurate description of both the structural and electronic properties of typical ferroelectric oxides.

Developing an accurate simulation method for the electrochemical stability of solids, as well as understanding the physics related with its accuracy, is critically important for improving the performance of compounds and predicting the stability of new materials in aqueous environments. Herein we propose a workflow for the accurate calculation of first-principles electrochemical phase (Pourbaix) diagrams. With this scheme, we study the electrochemical stabilities of Ti and Ti oxides using density-functional theory. First, we find the accuracy of an exchange-correlation functional in predicting formation energies and electrochemical stabilities is closely related with the electronic exchange interaction therein. Second, the metaGGA and hybrid functionals with a more precise description of the electronic exchange interaction lead to a systematic improvement in the accuracy of the Pourbaix diagrams. Furthermore, we show that accurate Ti Pourbaix diagrams also require that thermal effects are included through vibrational contributions to the free energy. We then use these diagrams to explain various experimental electrochemical phenomena for the Ti--O system, and show that if experimental formation energies for Ti oxides, which contain contributions from defects owing to their generation at high (combustion) temperatures, are directly used to predict room temperature Pourbaix diagrams then significant inaccuracies result. In contrast, the formation energies from accurate first-principles calculations, e.g., using metaGGA and hybrid functionals, are found to be more reliable. Finally to facilitate the future application of our accurate electrochemical phase equilibria diagrams, the variation of the Ti Pourbaix diagrams with aqueous ion concentration is also provided.

Previous work on the physical content of exchange correlation functionals that depend on both charge and spin densities is extended to elemental transition metals and a wider range of perovskite transition metal oxides. A comparison of spectra and magnetic moments calculated using exchange correlation functionals depending on charge density only or on both charge and spin densities, as well as the $+U$ and $+J$ extensions of these methods confirms previous conclusions that the spin-dependent part of the exchange correlation functional provides an effective Hund's interaction acting on the transition metal $d$ orbitals. For the local spin density approximation and spin-dependent Perdew-Burke-Ernzerhof generalized gradient approximation, the effective Hund's exchange is found to be larger than 1 eV. The results indicate that at least as far as applications to transition metals and their oxides are concerned, $+U$, $+J$ and +dynamical mean field theory extensions of density functional theory should be based on exchange-correlation functionals of charge density only.

Density functional theory calculations were carried out for three entropic rocksalt oxides, (Mg0.1Co0.1Ni0.1Cu0.1Zn0.1)O0.5, termed J14, and J14 Li and J14 Sc, to understand the role of charge neutrality and electronic states on their properties, and to probe whether simple expressions may exist that predict stability. The calculations predict that the average lattice constants of the ternary structures provide good approximations to that of the random structures. For J14, Bader charges are transferable between the binary, ternary, and random structures. For J14 Sc and J14 Li, average Bader charges in the entropic structures can be estimated from the ternary compositions. Addition of Sc to J14 reduces the majority of Cu, which show large displacements from ideal lattice sites, along with reduction of a few Co and Ni cations. Addition of Li to J14 reduces the lattice constant, consistent with experiment, and oxidizes some of Co as well as some of Ni and Cu. The Bader charges and spin-resolved density of states (DOS) for Co 3 in J14 Li are very different from Co 2, while for Cu and Ni the Bader charges form continuous distributions and the two DOS are similar for the two oxidation states. Experimental detection of different oxidation states may therefore be challenging for Cu and Ni compared to Co. Based on these results, empirical stability parameters for these entropic oxides may be more complicated than those for non-oxide entropic solids.

We investigate the behavior of oxygen vacancies in three different metal-oxide semiconductors (rutile and anatase TiO2, monoclinic WO3, and tetragonal ZrO2) using a recently proposed hybrid density-functional method in which the fraction of exact exchange is material-dependent but obtained ab initio in a self-consistent scheme. In particular, we calculate charge-transition levels relative to the oxygen-vacancy defect and compare computed optical and thermal excitation/emission energies with the available experimental results, shedding light on the underlying excitation mechanisms and related materials properties. We find that this novel approach is able to reproduce not only ground-state properties and band structures of perfect bulk oxide materials, but also provides results consistent with the optical and electrical behavior observed in the corresponding substoichiometric defective systems.

This project was dedicated to investigate and engineer novel properties of oxide based materials, nanostructures and devices with properties that are not available in bulk materials. The proposal is based on common interest and complementary expertise of two co-PIs specializing in synthesis and transport (Schuller) and nanoscaled characterization (Shpyrko). We aimed to demonstrate tunability and control of these properties by incorporating oxides in devices with innovative architecture. The extensive number of publications, in high impact journals and the large number of invited talks indicates that this is a very successful project, with a major impact on the field. This project is an important ingredient in at least five PhD theses, had the participation of 3 postdoctoral fellows and (no cost) contribution from visitors.

1Captain Jim

By Mary Grant Bruce

This book is about Norah Linton, her brother Jim, her father David and Jim's chum Wally from Australia. They all move to England during WWI because Jim and Wally want to fight in the war.<br /><br />When a Irish friend of the family dies, Norah inherits a big house in Surrey: Homewood. To keep up the Irishman's memory they want to use the house to help the war effort. They turn it into a home for "Tired People"--soldiers recovering from injuries, or soldiers on leave that have no family to go home to, can come here to have a good time and enjoy the country-side, so that they can go back to their regiments fully rested and restored.<br /><br />Unfortunately Jim and Wally are soon called upon to fight, leaving Norah and her father to take care of the Tired People. (Summary by wendy)

2Little Bush Maid

By Mary Grant Bruce

An Australian children's classic about life on a ranch around the same time of A Little Florida Lady, with a similarly plucky tomboy heroine. Also, like the latter story, expect some racial stereotyping of Asian and Aboriginal characters. (Summary by BellonaTimes)

Mary Grant Bruce was an Australian children's writer who spent one year collecting Aboriginal stories in Gippsland - a part of Victoria which it is thought had a dense population of the early Australians. Sadly, now there are no tribal people living, though their descendants are still around. This book contains 13 stories of the Gunaikurnai people, as told by their elders to the author. From the preface:<br> <em>Year by year the old black tribes are dying out, and many of their legends and beliefs are dying with them. These legends deal with the world as the blacks knew it; with the Bush animals and birds; the powers of storm, flood, fire, thunder, and magic, and the beings who they thought controlled these powers; with the sun, moon and stars; and with the life and death of men and women. <br> The folktales of a people are the story of its soul, and it would be a pity if the native races of our country were to vanish altogether before we had collected enough of their legends to let their successors know what manner of people lived in Australia for thousands of years before the white man came.</em> (From the Preface by Mary Grant Bruce with a little help from annise)

4Assault on Mount Everest, 1922

By Charles Granville Bruce, George Ingle Finch, Tom Longstaff, George Mallory, T. Howard Somervell and Francis Edward Younghusband

Personal narratives of climbing Mount Everest in 1922-1923. The expeditions did not reach the summit. The northern approach to the mountain was discovered by George Mallory and Guy Bullock on the initial 1921 British Reconnaissance Expedition. It was an exploratory expedition not equipped for a serious attempt to climb the mountain. With Mallory leading (and thus becoming the first European to set foot on Everest's flanks) they climbed the North Col to an altitude of 7,005 metres (22,982 ft). From there, Mallory espied a route to the top, but the party was unprepared for the great task of climbing any further and descended. The British returned for a 1922 expedition. George Finch climbed using oxygen for the first time. He ascended at a remarkable speed—290 metres (951 ft) per hour, and reached an altitude of 8,320 m (27,300 ft), the first time a human reported to climb higher than 8,000 m. Mallory and Col. Felix Norton made a second unsuccessful attempt. Mallory was faulted for leading a group down from the North Col which got caught in an avalanche. Mallory was pulled down too but survived. Seven native porters were killed. - Summary by Wikipedia

5Historic Ghosts and Ghost Hunters

By Henry Addington Bruce

The author describes popular ghost occurrences from a skeptical point of view, providing explanations based on recent scientific research (early 20th century), primarily in the field of psychology, like suggestion and hallucinations, using also his beliefs on mesmerism and telepathy. He finishes his book with a brief mention of ghost hunters and researchers into psychic phenomena. - Summary by Rapunzelina

6Benjamin Franklin: Self-Revealed, Volume 1

By William Cabell Bruce

His life was like a full five-act play—prophetic prologue and stately epilogue, and swelling scene imposed upon swelling scene, until the tallow chandler's son, rising from the humblest levels of human fortune to the highest by uninterrupted gradations of invincible success, finally becomes the recipient of such a degree of impressive homage as has rarely been paid to anyone by the admiration and curiosity of mankind. (from Introduction)

7Benjamin Franklin: Self-Revealed, Volume 2

By William Cabell Bruce

His life was like a full five-act play—prophetic prologue and stately epilogue, and swelling scene imposed upon swelling scene, until the tallow chandler's son, rising from the humblest levels of human fortune to the highest by uninterrupted gradations of invincible success, finally becomes the recipient of such a degree of impressive homage as has rarely been paid to anyone by the admiration and curiosity of mankind. (from Introduction)

Stories of Confederate soldiers of the Civil War that share the vivid accounts of valor, resolve, loyalty, and endurance. Using historical records and firsthand testimonies, this book offers an account of men facing overwhelming odds while performing deeds of cunning, daring, courage, and heroism on the battlefield. - Summary by Barry Eads