Study of specific absorption rate of strontium doped lanthanum manganite nanoparticles for self-controlled hyperthermia applications

Magnetic and magnetothermal properties of strontium doped lanthanum manganite La1−xSrxMnO3 nanoparticles have been studied with the strontium concentration x varying between 0.15 and 0.45. La1−xSrxMnO3 nanoparticles were prepared by the citrate gel route. XRD results show that all samples exhibit the characteristic perovskite structure with average particle sizes between 33 and 44 nm. Adiabatic magnetothermia measurements were carried out in an RF magnetic field of 800 A/m and 214 kHz. Both magnetic and thermomagnetic behaviors are governed by the strontium content of the samples. The saturation magnetization, Curie temperature and specific absorption rate (SAR) vary non-monotonically with x. The SAR of the nanoparticles has been calculated using the linear response theory and good agreement with the experimental data has been observed. The intrinsic loss power (ILP) has been obtained from the SAR values. ILP values of our samples are comparable to those of magnetite.