Scientific Reports 4: Article number: 4120 ; published online: 18 February 2014; updated: 30 June 2015

Makoto Tachibana was omitted from the author list in the original version of this Article. This has been corrected in the PDF and HTML versions of the Article.

The Author Contributions section now reads:

‘B.S. prepared the samples, carried out PXRD, electrical resistivity, magnetic susceptibility and heat capacity measurements. C.C. performed STEM measurements. M.P. carried out STM and STS experiments. T.C.H., W.R.II and S.D.W. carried out neutron diffraction experiments. K.F., M.T. and B.D.G. contributed to X-ray diffraction experiments. A.S.S. initiated the project, assisted with the physical property measurements, supervised the experiments, analyzed the data and wrote the paper. All authors reviewed the manuscript. Everyone contributed to the data analysis, discussions and writing of the manuscript.’