Neutron diffraction evidence for kinetic arrest of first-order magneto-structural phase transitions in some functional magnetic materials

Autor: Siruguri, V., Babu, P. D., Kaushik, S. D., Biswas, Aniruddha, Sarkar, S. K., Madangopal, K., Chaddah, P.
Rok vydání: 2013
Předmět:
Zdroj: J. Phys.: Condens. Matter 25 (2013) 496011
Druh dokumentu: Working Paper
DOI: 10.1088/0953-8984/25/49/496011
Popis: Neutron diffraction measurements, performed in presence of an external magnetic field, have been used to show structural evidence for the kinetic arrest of the first-order phase transition from (i) the high temperature austenite phase to the low temperature martensite phase in the magnetic shape memory alloy Ni37Co11Mn42.5Sn9.5, (ii) the higher temperature ferromagnetic phase to the lower temperature antiferromagnetic phase in the half-doped charge ordered compound La0.5Ca0.5MnO3 and (iii) the formation of a glass-like arrested state (GLAS). The CHUF (cooling and heating under unequal fields) protocol has been used to establish phase coexistence of metastable and equilibrium states of GLAS and also to demonstrate the devitrification of the arrested metastable states in the neutron diffraction patterns. We also explore the field-temperature (H,T) phase diagram for the two compounds, which depicts the kinetic arrest line TK(H). TK is seen to increase as H increases.
Comment: This submission adds considerable amount of data on a new material to arXiv:1211.0238, and has been accepted as a regular paper in Journal of Physics: Condensed Matter
Databáze: arXiv