The electronic structure of NaFeAs is studied with angle resolved photoemission spectroscopy on high quality single crystals. Large portions of the band structure start to shift around the structural transition temperature, and smoothly evolve as the temperature lowers through the spin density wave transition. Moreover, band folding due to magnetic order emerges around structural transition. Our observation provides direct evidence that the structural and magnetic transitions share the same origin, and are both driven by the electronic structure reconstruction in Fe-based superconductors, instead of Fermi surface nesting.
@article{arxiv.1001.2981,
title = {Electronic structure reconstruction: the driving force behind the magnetic and structural transitions in NaFeAs},
author = {C. He and Y. Zhang and B. P. Xie and X. F. Wang and L. X. Yang and B. Zhou and F. Chen and M. Arita and K. Shimada and H. Namatame and M. Taniguchi and X. H. Chen and J. P. Hu and D. L. Feng},
journal= {arXiv preprint arXiv:1001.2981},
year = {2011}
}