Projects per year
Abstract
The lifting of dxz-dyz orbital degeneracy is often considered a hallmark of the nematic phase of Fe-based superconductors, including FeSe, but its origin is not yet understood. Here we report a high resolution Angle-Resolved Photoemission Spectroscopy study of single crystals of FeSe, accounting for the photon-energy dependence and making a detailed analysis of the temperature dependence. We find that the hole pocket undergoes a fourfold-symmetry-breaking distortion in the nematic phase below 90K, but in contrast the changes to the electron pockets do not require fourfold symmetry-breaking. Instead, there is an additional separation of the existing dxy and dxz/yz bands - which themselves are not split within resolution. These observations lead us to propose a new scenario of "unidirectional nematic bond ordering" to describe the low-temperature electronic structure of FeSe, supported by a good agreement with 10-orbital tight binding model calculations.
Original language | English |
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Article number | 201107(R) |
Number of pages | 6 |
Journal | Physical Review B |
Volume | 94 |
Issue number | 20 |
DOIs | |
Publication status | Published - 11 Nov 2016 |
Projects
- 1 Finished
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Theoretical and experimental study of electronic and magnetic properties of the iron-base superconductors
Eschrig, M. (PI)
21/09/15 → 20/03/19
Project: Research