Electronic properties, low-energy Hamiltonian and superconducting instabilities in CaKFe4_4As4_4

We analyze the electronic properties of the recently discovered stoichiometric superconductor CaKFe$_4$As$_4$ by combining an ab initio approach and a projection of the band structure to a lowenergy tight-binding Hamiltonian, based on the maximally localized Wannier orbitals of the 3d Fe states. We identify the key symmetries as well as differences and similarities in the electronic structure between CaKFe$_4$As$_4$ and the parent systems CaFe$_2$As$_2$ and KFe$_2$As$_2$. In particular, we find CaKFe4As4 to have a significantly more quasi-two-dimensional electronic structure than the latter systems. Finally, we study the superconducting instabilities in CaKFe$_4$As$_4$ by employing the leading angular harmonics approximation (LAHA) and find two potential A$_{1g}$-symmetry representation of the superconducting gap to be the dominant instabilities in this system.Comment: 17 pages, 10 figure

Surface temperature mapping with infrared photographic pyrometry for turbine cooling investigations

Surface temperature mapping with infrared photographic pyrometry for turbine cooling investigation

Book review: the crises of microcredit edited by Isabelle Guérin, Marc Labie and Jean-Michel Servet

Do microfinance initiatives offer a panacea for poverty? In The Crises of Microcredit, editors Isabelle Guérin, Marc Labie and Jean-Michel Servet present a set of essays that examines the emergent problems in the microfinance sector. While the book will be of use to those wanting to understand how an apparent miracle cure now seems shrouded in crisis, Jason Hickel argues that the book does not fully explore the structural issues that render microcredit a fundamentally flawed means of enabling development and solving global poverty

Book review: the new extractivism: a post-neoliberal development model or imperialism of the twenty-first century? edited by Henry Veltmeyer and James Petras

The New Extractivism aims to address a fundamental dilemma faced by governments in Latin America: to pursue, or not, a development strategy based on resource extraction in the face of immense social and environmental costs, not to mention mass resistance from the people negatively affected by it. This book offers a persuasive antidote to the misplaced optimism about Latin America that many progressives have bought into, writes Jason Hickel