Ferromagetism demises SC in overdoped LSCO ?

The phase diagram of cuprate superconductors is as perplexing as one can imagine. It is like winning a holy grail to theoretically explicate this diagram. One feature in it is the SC dome: the SC phase survives only a segment between x1 and x2. Much attention has been paid to the regime around x1, while little to that around x2. A basic question is, what destroys SC in the course of overdoping ? Experiments actually have found no traces of what can be seen in the vicinity of x1, the Mottness behaviors showing significant AFM fluctuations. Some claimed that, the compound becomes a normal Fermi liquid beyond x2, which is however questioned for several reasons [http://www.pnas.org/content/104/15/6123.full.pdf]. A novel proposal surmised that, there is a new order, a ferromagnetic order, that competes with SC [http://www.pnas.org/content/104/15/6123.full.pdf]. Their proposal finds advocate from an upturn in the uniform magnetic susceptibility that is usually associated with FM correlations. More interestingly, a recent experiment claimed a direct observation of this FM phase [http://www.pnas.org/content/107/40/17131.full.pdf]. This makes the x2-region very fashionable.