Discovery of mesoscopic nematicity wave in iron-based superconductors

Abstract

Nematicity is ubiquitous in electronic phases of high transition temperature superconductors, particularly in iron-based superconductors (IBSCs). Order parameter that characterizes the nematic phase has been investigated in momentum space, but its real-space arrangement remains largely unclear. We use linear dichroism (LD) in low-temperature laser-photoemission electron microscope to map out the nematic order parameter of nonmagentic FeSe and antiferromagnetic BaFe2(As0.87P0.13)2. In contrast to the structural domains that have atomic-scale domain walls, the LD patterns in both materials show peculiar sinusoidal waves of electronic nematicity with mesoscopic wavelength. The analysis reveals that the nematic order has an extremely long coherence length, more than 1000 times longer than the unit cell. Our direct visualization of electronic spatial variation uncovers a new fundamental aspect of quantum liquid crystalline states of correlated electrons in IBSCs.

15 pages, 4 figures, Supplementary materials

References in corpus (7)

• Evidence for an electron nematic phase transition in underdoped iron pnictide superconductors
• Electronic liquid crystal state in the high-temperature superconductor YBCO(6.45)
• Nematic and meta-nematic transitions in the iron pnictides
• Scale-free structural organization of oxygen interstitials in La2CuO4+y
• Thermodynamic evidence for nematic phase transition at the onset of pseudogap in YBa${}_2$Cu${}_3$O${}_y$
• Sliding charge density wave in manganites
• Quantitative characterization of short-range orthorhombic fluctuations in FeSe through pair distribution function analysis

Cited by in corpus (9)

• FeSe and the missing electron pocket problem
• Electronic Stripe Patterns Near the Fermi Level of Tetragonal Fe(Se,S)
• Defect-induced electronic smectic state at the surface of nematic materials
• Diverse Exotic Orders and Fermiology in Fe-based Superconductors: A Unified Mechanism for $B_{1g}/B_{2g}$ Nematicity in FeSe/(Cs,Rb)Fe${}_2$As${}_2$ and Smectic Order in BaFe${}_2$As${}_2$
• Enhanced Phonon-Phonon Interactions and Weakened Electron-Phonon Coupling in Charge-Density-Wave Topological Semimetal EuAl4 with a Possible Intermediate Electronic State
• Transport evidence for twin-boundary pinning of superconducting vortices in FeSe
• Coherence Length of Electronic Nematicity in Iron-Based Superconductors
• Atomic-scale imaging of electronic nematicity in ferropnictides
• Energy-Resolved Real-Space Imaging of Orbital Nematicity in an Fe-Based Superconductor