In-Plane Electronic Anisotropy of Underdoped ___122___ Fe-Arsenide Superconductors Revealed by Measurements of Detwinned Single Crystals

Download or read book In-Plane Electronic Anisotropy of Underdoped ___122___ Fe-Arsenide Superconductors Revealed by Measurements of Detwinned Single Crystals written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The parent phases of the Fe-arsenide superconductors harbor an antiferromagnetic ground state. Significantly, the Neel transition is either preceded or accompanied by a structural transition that breaks the four fold symmetry of the high-temperature lattice. Borrowing language from the field of soft condensed matter physics, this broken discrete rotational symmetry is widely referred to as an Ising nematic phase transition. Understanding the origin of this effect is a key component of a complete theoretical description of the occurrence of superconductivity in this family of compounds, motivating both theoretical and experimental investigation of the nematic transition and the associated in-plane anisotropy. Here we review recent experimental progress in determining the intrinsic in-plane electronic anisotropy as revealed by resistivity, reflectivity and ARPES measurements of detwinned single crystals of underdoped Fe arsenide superconductors in the '122' family of compounds.