Charge stripe structure in Fe1+xTe by STM

• We find the charge stripe in the iron-based superconductor for the first time.
• The SDW gap on mean field theory was found by spectroscopy at charge stripe phase.
• A new type charge stripe is discovered in iron-based superconductor.

The electronic state of Fe1.17Te was investigated with atomic resolution by using STM. We discovered a charge stripe structure at 7.8 K for the first time. The wave vector of the charge stripe structure is along the a-axis or b-axis. Furthermore we found that the charge stripe occurred at the Fe layer. We also found a 9 meV gap structure on the Fermi surface by STS. The gap size is consistent with the mean field approximation with SDW transition temperature of 58 K.