The study of structure, magnetism, electricity, and their correlations at martensitic transition for magnetostriction system Cu1−<i>x</i>Mn<i>x</i>NMn3 (0 ≤ <i>x</i> ≤ 0.5)

Abstract

The antiperovskite functional compound CuNMn3 exhibits magnetostriction below the non-collinear ferromagnetic (FM)-paramagnetic (PM) transition (accompanied by a martensitic transformation). After the substitution of Mn for Cu, martensitic transformation is decoupled from FM transition. Meanwhile, the tetragonality of the martensitic phase and the magnetostriction are weakened. The combined analysis indicates that the spin, charge, and lattice are closely coupled around martensitic transformation temperature (TMS). The low-temperature martensitic phase is associated with a metastable magnetic state characterized by small magnetocrystalline anisotropy. Additionally, the depression of TMS with introducing the Mn dopant is revelatory for the development of low-temperature negative thermal expansion material.