Andreas Eich

Atom-specific spin mapping and buried topological states in a homologous series of topological insulators

A topological insulator is a state of quantum matter that, while being an insulator in the bulk, hosts topologically protected electronic states at the surface. These states open the opportunity to realize a number of new applications in spintronics and quantum computing. To take advantage of their peculiar properties, topological insulators should be tuned in such a way that ideal and isolated Dirac cones are located within the topological transport regime without any scattering channels. Here we report ab-initio calculations, spin-resolved photoemission and scanning tunnelling microscopy experiments that demonstrate that the conducting states can effectively tuned within the concept of a homologous series that is formed by the binary chalcogenides (Bi(2)Te(3), Bi(2)Se(3) and Sb(2)Te(3)), with the addition of a third element of the group IV.

Stabilisation of a Highly Reactive Bis(μ-oxo)dicopper(III) Species at Room Temperature by Electronic and Steric Constraint of an Unconventional Nitrogen Donor Ligand

Herein we present an innovative combination of EXAFSspectroscopy and resonant Raman scattering for the charac-terisation of the ground state and structural dynamics of athermally stable binuclear bisACHTUNGRE(m-oxo) dicopperACHTUNGRE(III) species.Peralkylated bis(guanidine)-based ligands are used in thesynthesis of this compound.

UV-light-induced conversion and aggregation of prion proteins.

Increasing evidence suggests a central role for oxidative stress in the pathology of prion diseases, a group of fatal neurodegenerative disorders associated with structural conversion of the prion protein (PrP). Because UV-light-induced protein damage is mediated by direct photo-oxidation and radical reactions, we investigated the structural consequences of UVB radiation on recombinant murine and human prion proteins at pH 7.4 and pH 5.0. As revealed by circular dichroism and dynamic light scattering measurements, the observed PrP aggregation follows two independent pathways: (i) complete unfolding of the protein structure associated with rapid precipitation or (ii) specific structural conversion into distinct soluble beta-oligomers. The choice of pathway was directly attributed to the chromophoric properties of the PrP species and the susceptibility to oxidation. Regarding size, the oligomers characterized in this study share a high degree of identity with oligomeric species formed after structural destabilization induced by other triggers, which significantly strengthens the theory that partly unfolded intermediates represent initial precursor molecules directing the pathway of PrP aggregation. Moreover, we identified the first suitable photo-trigger capable of inducing refolding of PrP, which has an important biotechnological impact in terms of analyzing the conversion process on small time scales.

Crystalline and electronic structure of single-layer TaS2

Single-layer

Absence of superconductivity in ultrathin layers of FeSe synthesized on a topological insulator

{\mathrm{TaS}}_{2}

Response of the topological surface state to surface disorder in TlBiSe2

is epitaxially grown on Au(111) substrates. The resulting two-dimensional crystals adopt the

Design and performance of an ultra-high vacuum spin-polarized scanning tunneling microscope operating at 30 mK and in a vector magnetic field

1H

Characterization of the optically excited state of a bis (μ-oxo)-dicopper(III) species mimicking the hemocyanin and tyrosinase active sites

polymorph. The electronic structure is determined by angle-resolved photoemission spectroscopy and found to be in excellent agreement with density functional theory calculations. The single-layer

Electronic screening-enhanced hole pairing in two-leg spin ladders studied by high-resolution resonant inelastic x-ray scattering at Cu M edges.

{\mathrm{TaS}}_{2}

Pseudodoping of Metallic Two-Dimensional Materials by The Supporting Substrates

is found to be strongly