Electronic structure and H−T phase diagram of Eu(Fe1−xRhx)<

Abstract

The iron-based superconductors represent a promising platform for high-temperature superconductivity, but the interactions underpinning their pairing present a puzzle. The EuFe2As2 family is unique among these materials for having magnetic order which onsets within the superconducting state, just below the superconducting transition. Superconductivity and magnetic order are normally antagonistic and often vie for the same unpaired electrons, but in this family the magnetism arises from largely localized Eu moments and they coexist, with the competition between these evenly-matched opponents leading to reentrant superconducting behavior. To help elucidate the physics in this family and the interactions between the magnetic order and superconductivity, we investigate the H-T phase diagram near optimal Rh doping through specific heat, resistivity, and magnetization measurements, and study the electronic structure by angular-resolved photoemission spectroscopy. The competition between the Eu and FeAs layers may offer a route to directly accessing the electronic structure under effective magnetic fields via ARPES, which is ordinarily a strictly zero-field technique. arXiv:1905.11554v2 [cond-mat.supr-con]

Nonlinear Nernst effect in bilayer WTe2

“…We calculate and make experimental predictions for the NLANE coefficient for its dependence on temperature, spin-orbit coupling, tilting, inter-layer coupling, and chemical potential for the bilayer WTe 2 , in which signatures of NLAHE have been observed recently. In addition to the Berry curvature dipole contribution, disorder mediated effects such as non-linear side-jump and skew scatterings from impurities that contribute to the nonlinear anomalous Hall effect 48,49,51,70,71 , may also contribute to non-linear anomalous Nernst effect. These effects are beyond the scope of this paper and are left for future study.…”

“…The underlying physics associated with the non-linear anomalous Hall effect (NLAHE) has been shown to be related to the band structure properties. Several candidate materials with low crystalline symmetries have been proposed to exhibit a finite or enhanced BCD [47][48][49][50][51] .…”