The Forward Tracking: Algorithm and Performance Studies

This note describes the so-called Forward Tracking. This algorithm uses as input track seeds reconstructed in the VELO (Vetex Locator) and searches for associated tracks in the inner and outer tracker of the T stations based on a Hough Transformation approach. We describe in detail the implementation of the algorithm as it is in Brunel version 30r14 and the according performance on DC06 data

Numerical comparison of two approaches for the study of phase transitions in small systems

We compare two recently proposed methods for the characterization of phase transitions in small systems. The validity and usefulness of these approaches are studied for the case of the q=4 and q=5 Potts model, i.e. systems where a thermodynamic limit and exact results exist. Guided by this analysis we discuss then the helix-coil transition in polyalanine, an example of structural transitions in biological molecules.Comment: 16 pages and 7 figure

Partnership, ownership and control: the impact of corporate governance on employment relations

Prevailing patterns of dispersed share ownership and rules of corporate governance for UK listed companies appear to constrain the ability of managers to make credible, long-term commitments to employees of the kind needed to foster effective labour-management partnerships. We present case study evidence which suggests that such partnerships can nevertheless emerge where product market conditions and the regulatory environment favour a stakeholder orientation. Proactive and mature partnerships may also be sustained where the board takes a strategic approach to mediating between the claims of different stakeholder groups, institutional investors are prepared to take a long-term view of their holdings, and strong and independent trade unions are in a position to facilitate organisational change

Single- and two-particle observables in the Emery model: a dynamical mean-field perspective

We compare the dynamical mean-field descriptions of the single-band Hubbard model and the three-band Emery model at the one- and two-particle level for parameters relevant to high-Tc superconductors. We show that even within dynamical mean-field theory, accounting solely for temporal fluctuations, the intrinsic multi-orbital nature of the Emery model introduces effective non-local correlations. These lead to a non-Curie-like temperature-dependence of the magnetic susceptibility, also seen in nuclear magnetic resonance experiments in the pseudogap regime by M. Avramovska, et al. [Journal of Superconductivity and Novel Magnetism 33, 2621 (2020)]. We demonstrate the agreement of our results with these experiments for a large range of dopings and trace back the effective non-local correlations to an emerging oxygen-copper singlet by analyzing a minimal finite-size cluster model. Despite this correct description of the hallmark of the pseudogap at the two-particle level, i.e., the drop in the Knight shift of nuclear magnetic resonance, dynamical mean-field theory fails to properly describe the spectral properties of the pseudogap.Comment: 7 pages, 7 figure

Pseudogap of metallic layered nickelate R2-xSrxNiO4 (R=Nd, Eu) crystals measured using angle-resolved photoemission spectroscopy

We have investigated charge dynamics and electronic structures for single crystals of metallic layered nickelates, R2-xSrxNiO4 (R=Nd, Eu), isostructural to La2-xSrxCuO4. Angle-resolved photoemission spectroscopy on the barely-metallic Eu0.9Sr1.1NiO4 (R=Eu, x=1.1) has revealed a large hole surface of x2-y2 character with a high-energy pseudogap of the same symmetry and comparable magnitude with those of underdoped (x<0.1) cuprates, although the antiferromagnetic interactions are one order of magnitude smaller. This finding strongly indicates that the momentum-dependent pseudogap feature in the layered nickelate arises from the real-space charge correlation.Comment: 4 pages, 4 figures. Accepted in Physical Review Letter

Inequivalent routes across the Mott transition in V2O3 explored by X-ray absorption

The changes in the electronic structure of V2O3 across the metal-insulator transition induced by temperature, doping and pressure are identified using high resolution x-ray absorption spectroscopy at the V pre K-edge. Contrary to what has been taken for granted so far, the metallic phase reached under pressure is shown to differ from the one obtained by changing doping or temperature. Using a novel computational scheme, we relate this effect to the role and occupancy of the a1g orbitals. This finding unveils the inequivalence of different routes across the Mott transition in V2O

Turning a nickelate Fermi surface into a cuprate-like one through heterostructuring

Using the local density approximation and its combination with dynamical mean-field theory, we show that electronic correlations induce a single-sheet, cuprate-like Fermi surface for hole-doped 1/1 LaNiO3 /LaAlO3 heterostructures, even though both eg orbitals contribute to it. The Ni 3d 3z^2-1 orbital plays the role of the axial Cu 4s-like orbital in the cuprates. These two results indicate that "orbital engineering" by means of heterostructuring should be possible. As we also find strong antiferromagnetic correlations, the low-energy electronic and spin excitations in nickelate heterostructures resemble those of high-temperature cuprate superconductors.Comment: 4 pages, 3 figure