13,242 research outputs found
The Role of Carbonaceous Material in the Formation of Macraes Orogenic Gold Deposit, New Zealand
The PhD project investigated the role of carbonaceous material in the formation of Macraes orogenic gold deposits. It provided the first evidence that in-situ carbonaceous material directly contributes to Au incorporation into polyframboids which may provide the source of Au for the Macraes gold deposit; that carbonaceous material in mineralized rocks of gold deposit is most likely hydrothermally deposited and contributes to Au precipitation indirectly; and that dodecanethiol may transport Au in hydrothermal systems
Coupled topological flat and wide bands: Quasiparticle formation and destruction
Flat bands amplify correlation effects and are of extensive current interest.
They provide a platform to explore both topology in correlated settings and
correlation physics enriched by topology. Recent experiments in correlated
kagome metals have found evidence for strange-metal behavior. A major
theoretical challenge is to study the effect of local Coulomb repulsion when
the band topology obstructs a real-space description. In a variant to the
kagome lattice, we identify an orbital-selective Mott transition for the first
time in any system of coupled topological flat and wide bands. This was made
possible by the construction of exponentially localized and Kramers-doublet
Wannier functions, which in turn leads to an effective Kondo lattice
description. Our findings show how quasiparticles are formed in such coupled
topological flat-wide band systems and, equally important, how they are
destroyed. Our work provides a conceptual framework for the understanding of
the existing and emerging strange-metal properties in kagome metals and beyond.Comment: 30 pages, 6 figures. To appear in Science Advance
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