Bismuth-substituted lanthanum manganite for bolometric applications

In this study, we are exploring the use of perovskite manganese oxide for bolometric applications. To obtain a large temperature coefficient of resistance (TCR: defined as 1/R dR/dT) at near-room temperature, we formed (Bi, La)_1-xSr_xMnO₃ (BLSMO) bulk samples. The substituted Bi in samples function to reduce the crystallization temperature and to eliminate the ferromagnetic phase. In this report, we discuss the issues related to the influence of the substituted Bi on features such as the surface morphologies, crystallinities and electrical transport properties. For the samples, the temperature dependence of resistivity indicates thermally activated behavior like that of a semiconductor, and a higher activation energy implies a larger TCR value. The maximum TCR value of the samples was 3.6%/K at room temperature.