Electrical, thermal and magnetic studies on Bi-substituted LSMO manganites

• The Bi-doped compounds follow small polaron hopping model in high temperature range.
• Electrical resistivity data shows evidences about existence of magnetic polarons.
• MR and TCR increase with Bi-content.
• Potential bolometer and magnetic sensing materials.

In the present investigation detailed electrical, magnetic and thermoelectric measurements on Bi-doped L0.6−xBixSr0.4MnO3 (0≤x≤0.3) manganites have been done. All the samples are single phased. The metal-insulator transition temperatures (TMI) as well as the Curie temperature (TC) are both found to decrease with Bi-content. Magneto-resistance (MR) data shows that MR (%) increases with Bi-content thereby showing it can be used in magnetic memory based devices. Resistivity data shows that small polaron hopping (SPH) model is valid in high temperature regime. Low temperature resistivity data depicts that electron–electron scattering is mainly responsible for the conduction mechanism. High temperature thermoelectric power (TEP) data reaffirms the validity of SPH model.