2020/05/28 by Sambhu Charan Das, Das, S. C., Jhuma Sannigrahi +13
Materials Science · Physics and Astronomy · #Magnetic Properties and Applications #Shape Memory Alloy Transformations #Magnetic properties of thin films
paper · pdf · doi:10.48550/arxiv.2005.13909
We have investigated the detailed magnetic structure of a Fe-doped MnNiGe alloy of nominal composition MnNi0.75Fe0.25Ge by ambient and high pressure (6 kbar) neutron powder diffraction study. The alloy undergoes a martensitic phase transition between 230 K and 275 K. The low-temperature martensite phase orders antiferromagnetically with helical modulation of Mn-spins. At 1.5 K, the incommensurate propagation vector \bf k is found to be (0.1790(1),0,0), and it remains almost unchanged with temperature under ambient condition. The Application of external pressure (P) reduces the martensitic transition temperature and results in a significant change in the incommensurate magnetic propagation vector. At 10 K, with 6 kbar of external pressure, the incommensurate magnetic structure of the alloy stabilizes with \bf k = (0.1569(1),0,0). Interestingly, the strong temperature dependence of \bf k in the presence of external P has also been observed.