We investigate the ultra-sharp jump in the isothermal magnetization and the resistivity in the polycrystalline Sm0.5(Ca0.5−ySry)MnO3(y=0,0.1,0.2,0.25,0.3,0.5) compounds. The critical field (Hcr), required for the ultra-sharp jump, decreases with increase of `Sr' concentration, i.e. with increase of average A-site ionic radius ⟨rA⟩. The magnetotransport data indicate that the phase separation increases with the increase of ⟨rA⟩, i.e. with y. The dependency of Hcr with magnetic field sweep rate reveals that the ultra-sharp jump from antiferromagnetic (AFM) state to the ferromagnetic (FM) state is of martensitic in nature. Our two-band double exchange model Hamiltonian calculations show that the `Sr' doping induces the ferromagnetic clusters in the antiferromagnetic insulating phase and in turn reduces the critical field. In the end we present a phenomenological picture obtained from our combined experimental and theoretical study.
@article{arxiv.1903.11348,
title = {Effect of A-site ionic radius on metamagnetic transition in charge ordered $Sm_{0.5}(Ca_{0.5-y}Sr_{y})MnO_3$ compounds},
author = {Sanjib Banik and Kalpataru Pradhan and I. Das},
journal= {arXiv preprint arXiv:1903.11348},
year = {2019}
}