The physics of quantum materials is dictated by many-body interactions and mathematical
concepts such as symmetry and topology that have transformed our understanding of matter …

The response of the worldwide scientific community to the discovery in 2008 of
superconductivity at T c= 26 K in the Fe-based compound LaFeAsO1− x F x has been very …

In this review we describe the development of photoemission spectroscopy (PES) from the
first historic observations of the photoelectric effect by Hertz and Hallwachs to state-of-the-art …

This review focuses on the most important features of the 40 K superconductor MgB 2—the
weakly interacting multiple bands (the σ and π bands) and the distinct multiple …

This Colloquium is concerned with the superconducting state of new high-T c compounds
containing hydrogen ions (hydrides). Recently superconductivity with the record-setting …

Two-band superconductivity has become an important topic over the past ten years.
Extensive experimental and theoretical studies started with MgB 2 and are now focused on …

We have developed a low temperature ultrahigh resolution system for polarization
dependent angle-resolved photoemission spectroscopy (ARPES) using a vacuum ultraviolet …

Proposed by Ginzberg nearly 60 years ago, surface superconductivity refers to the emergent
phenomenon that the electrons on or near the surface of a material becomes …

The electronic properties of the carbon-substituted MgB 2 single crystals are reported. The
carbon substitution drops T c below 2 K. In-plane resistivity shows a remarkable increase in …

Superconductors are classified by their pairing mechanism and the coupling strength,
measured as the ratio of the energy gap, 2 Δ, to the critical temperature, T c. We present an …