Rotation of the dislocation grid in multilayer FeSe films and visualization of electronic nematic domains via orbital-selective tunneling

Abstract

Understanding the interplay of structural and electronic symmetry breaking in Fe-based high temperature superconductors remains of high interest. In this work we grow strain-patterned multilayer FeSe thin films in a range of thicknesses using molecular beam epitaxy. We study the formation of electronic nematic domains and spatially-varying strain using scanning tunneling microscopy and spectroscopy. We directly visualize the formation of edge dislocations that give rise to a two-dimensional edge dislocation network in the films. Interestingly, we observe a 45 degree in-plane rotation of the dislocation network as a function of film thickness, yielding antisymmetric strain along different directions. This results in different coupling ratios between electronic nematic domains and antisymmetric strain. Lastly, we are able to distinguish between different orthogonal nematic domains by revealing a small energy-dependent difference in differential conductance maps between the two regions. This could be explained by orbital-selective tip-sample tunneling. Our observations bring new insights into the dislocation network formation in epitaxial thin films and provide another nanoscale tool to explore electronic nematicity in Fe-based superconductors.

References in corpus (12)

• Spin density wave anomaly at 140 K in the ternary iron arsenide BaFe2As2
• Evidence for an electron nematic phase transition in underdoped iron pnictide superconductors
• Lattice symmetry breaking in cuprate superconductors: Stripes, nematics, and superconductivity
• Lattice and magnetic instabilities in CaFe2As2: A single crystal neutron diffraction study
• Lifting of xz/yz orbital degeneracy at the structural transition in detwinned FeSe
• Nematicity, magnetism and superconductivity in FeSe
• The key ingredients of the electronic structure of FeSe
• Observation of two distinct $d_{xz}/d_{yz}$ band splittings in FeSe
• Nanoscale decoupling of electronic nematicity and structural anisotropy in FeSe thin films
• Incommensurate smectic phase in close proximity to the high-Tc superconductor FeSe/SrTiO3
• Visualizing nematic transition and nanoscale suppression of superconductivity in Fe(Te,Se)
• Edge states at nematic domain walls in FeSe films

Cited by in corpus (3)

• Nanoscale visualization of the thermally-driven evolution of antiferromagnetic domains in FeTe thin films
• Higher-order epitaxy: A pathway to suppressing structural instability and emergent superconductivity
• Nanoscale strain manipulation of smectic susceptibility in kagome superconductors