Field-induced first-order ferromagnetic transition in (La0.8Eu0.2)4/3Sr5/3Mn2O7 single crystal

Although the content of Eu in the single crystal (La0.8Eu0.2)(4/3)Sr5/3Mn2O7 is very small, the effects of Eu ions on the magnetic and transport properties are quite evident at low temperature due to the large size difference between Eu and La ions, compared with the crystal's parent compound La5/3Sr4/3Mn2O7. The sharp jumps in M(H) and rho(H) curves suggest that a first-order Field-induced transition from magnetically disorder state to 3D long-range ferromagnetic metallic state takes place at 2 K. Both resistivity and magnetization dependents on the magnetic history and clearly demonstrate hysteretic behaviors. These results indicate that the system has a very fragile ground state and the local lattice distortions in bilayer manganites play an important role in the physical properties.