Dirty Peierls transition to stripe phase in manganites

The nature of the phase transitions in La$_{0.48}$Ca$_{0.52} $MnO$_3$ and Pr$_{0.48}$Ca$_{0.52}$MnO$_3$ has been probed using heat capacity and magnetisation measurements. The phase transition associated with the onset of the stripe phase has been identified as a second order transition which can be very well fitted by the model of a Peierls transition in a disordered system (a `dirty' Peierls transition). We demonstrate that this model can also be applied to other systems (such as alpha- Uranium) in which Peierls transitions occur.