Transition in NiMnSn and NiMnIn

Magneto-transport, specific heat, magneto-striction and temperature dependent UV photoemission are used to explore the martensite transition of the ferromagnetic shape memory alloys Ni$_{x}$Mn$_{y}$In$_{z}$ and Ni$_{x}$Mn$_{y}$Sn$_{z}$. Comparisons will be made to a previous work\footnote{Opeil, et al. \textit{Physical Review Letters} \textbf{100}, 165703 (2008).} on the stoichiometric single crystal Ni$_{2}$MnGa which reveals a temperature (235 \underline {$>$} T \underline {$>$} 190 K) and field dependent (0 -- 1 T) positive/negative magneto-resistance slope. Our experimental results will be discussed in light of a possible pseudo-gap formation coincident with the martensite transition in the two off-stoichiometric alloys.