Magnetic-Field-Induced Step-like Transitions in Mn-Site Doped Manganites

An experimental study of the low T magnetic field dependence of the magnetization, specific heat and resistivity for an orbital and charge-ordered perovskite manganite doped in the Mn-site is presented. Well-defined steps are found in all these three physical properties. The abruptness of these jumps for T<10 K suggests some similarities to the Barkhausen effect and to the martensitic transition. This is a new illustration of the rich physics related to the phase separation.