Protecting the past for the public good: archaeology and Australian heritage law

Archaeological remains have long been recognised as fragile evidence of the past, which require protection. Legal protection for archaeological heritage has existed in Australia for more than thirty years but there has been little analysis of the aims and effectiveness of that legislation by the archaeological profession. Much Australian heritage legislation was developed in a period where the dominant paradigm in archaeological theory and practice held that archaeology was an objective science. Australian legislative frameworks continue to strongly reflect this scientific paradigm and contemporary archaeological heritage management practice is in turn driven by these legislative requirements. This thesis examines whether archaeological heritage legislation is fulfilling its original intent. Analysis of legislative development in this thesis reveals that legislators viewed archaeological heritage as having a wide societal value, not solely or principally for the archaeological community. Archaeological heritage protection is considered within the broader philosophy of environmental conservation. As an environmental issue, it is suggested that a ‘public good’ conservation paradigm is closer to the original intent of archaeological heritage legislation, rather than the “scientific” paradigm which underlies much Australian legislation. Through investigation of the developmental history of Australian heritage legislation it is possible to observe how current practice has diverged from the original intent of the legislation, with New South Wales and Victoria serving as case studies. Further analysis is undertaken of the limited number of Australian court cases which have involved substantial archaeological issues to determine the court’s attitude to archaeological heritage protection. Situating archaeological heritage protective legislation within the field of environmental law allows the examination of alternate modes of protecting archaeological heritage and creates opportunities for ‘public good’ conservation outcomes. This shift of focus to ‘public good’ conservation as an alternative to narrowly-conceived scientific outcomes better aligns with current public policy directions including the sustainability principles, as they have developed in Australia, as well as indigenous rights of self-determination. The thesis suggests areas for legal reforms which direct future archaeological heritage management practice to consider the ‘public good’ values for archaeological heritage protection

Weak and strong electronic correlations in Fe superconductors

In this chapter the strength of electronic correlations in the normal phase of Fe-superconductors is discussed. It will be shown that the agreement between a wealth of experiments and DFT+DMFT or similar approaches supports a scenario in which strongly-correlated and weakly-correlated electrons coexist in the conduction bands of these materials. I will then reverse-engineer the realistic calculations and justify this scenario in terms of simpler behaviors easily interpreted through model results. All pieces come together to show that Hund's coupling, besides being responsible for the electronic correlations even in absence of a strong Coulomb repulsion is also the origin of a subtle emergent behavior: orbital decoupling. Indeed Hund's exchange decouples the charge excitations in the different Iron orbitals involved in the conduction bands thus causing an independent tuning of the degree of electronic correlation in each one of them. The latter becomes sensitive almost only to the offset of the orbital population from half-filling, where a Mott insulating state is invariably realized at these interaction strengths. Depending on the difference in orbital population a different 'Mottness' affects each orbital, and thus reflects in the conduction bands and in the Fermi surfaces depending on the orbital content.Comment: Book Chapte

Non-stoichiometric oxide and metal interfaces and reactions

We have employed a combination of experimental surface science techniques and density functional calculations to study the reduction of TiO2(110) surfaces through the doping with submonolayer transition metals. We concentrate on the role of Ti adatoms in self doping of rutile and contrast the behaviour to that of Cr. DFT+U calculations enable identification of probable adsorption structures and their spectroscopic characteristics. Adsorption of both metals leads to a broken symmetry and an asymmetric charge transfer localised around the defect site of a mixed localised/delocalised character. Charge transfer creates defect states with Ti 3d character in the band gap at similar to 1-eV binding energy. Cr adsorption, however, leads to a very large shift in the valence-band edge to higher binding energy and the creation of Cr 3d states at 2.8-eV binding energy. Low-temperature oxidation lifts the Ti-derived band-gap states and modifies the intensity of the Cr features, indicative of a change of oxidation state from Cr3+ to Cr4+. Higher temperature processing leads to a loss of Cr from the surface region, indicative of its substitution into the bulk

Dynamical mean-field approach to materials with strong electronic correlations

We review recent results on the properties of materials with correlated electrons obtained within the LDA+DMFT approach, a combination of a conventional band structure approach based on the local density approximation (LDA) and the dynamical mean-field theory (DMFT). The application to four outstanding problems in this field is discussed: (i) we compute the full valence band structure of the charge-transfer insulator NiO by explicitly including the p-d hybridization, (ii) we explain the origin for the simultaneously occuring metal-insulator transition and collapse of the magnetic moment in MnO and Fe2O3, (iii) we describe a novel GGA+DMFT scheme in terms of plane-wave pseudopotentials which allows us to compute the orbital order and cooperative Jahn-Teller distortion in KCuF3 and LaMnO3, and (iv) we provide a general explanation for the appearance of kinks in the effective dispersion of correlated electrons in systems with a pronounced three-peak spectral function without having to resort to the coupling of electrons to bosonic excitations. These results provide a considerable progress in the fully microscopic investigations of correlated electron materials.Comment: 24 pages, 14 figures, final version, submitted to Eur. Phys. J. for publication in the Special Topics volume "Cooperative Phenomena in Solids: Metal-Insulator Transitions and Ordering of Microscopic Degrees of Freedom