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 …

Angle-resolved photoemission spectroscopy (ARPES)—an experimental technique based
on the photoelectric effect—is arguably the most powerful method for probing the electronic …

Superconductivity develops in metals upon the formation of a coherent macroscopic
quantum state of electron pairs. Iron pnictides and chalcogenides are materials that have …

Although the existence of nematic order in iron-based superconductors is now a well-
established experimental fact, its origin remains controversial. Nematic order breaks the …

Films of iron selenide (FeSe) one unit cell thick grown on strontium titanate (SrTiO3 or STO)
substrates have recently shown,,, superconducting energy gaps opening at temperatures …

Kamihara and coworkers' report of superconductivity at T c= 26 K in fluorine-doped
LaFeAsO inspired a worldwide effort to understand the nature of the superconductivity in this …

Since the discovery of high T c iron-based superconductors in early 2008, more than 15,000
papers have been published as a result of intensive research. This paper describes the …

The record superconducting transition temperature (T c) for the iron-based high-temperature
superconductors (Fe-HTS) has long been 56 K. Recently, in single-layer FeSe films grown …

The spontaneous reduction of rotational symmetry in a crystalline solid driven by an
electronic mechanism is referred to as electronic nematicity. This phenomenon—initially …

We present a comprehensive study of the evolution of the nematic electronic structure of
FeSe using high-resolution angle-resolved photoemission spectroscopy (ARPES), quantum …