We introduce a simple but powerful zero temperature Stoner model to explain
the unusual phase diagram of the ferromagnetic superconductor, UGe2. Triplet
superconductivity is driven in the ferromagnetic phase by tuning the majority
spin Fermi level through one of two peaks in the paramagnetic density of states
(DOS). Each peak is associated with a metamagnetic jump in magnetisation. The
twin peak DOS may be derived from a tight-binding, quasi-one-dimensional
bandstructure, inspired by previous bandstructure calculations.Comment: 9 pages, 9 figures, REVTeX 4. Version 2: updated references and
corrected typo