Near-Debye relaxation processes in La1-xSrxMnO3

Lanthanum manganite oxide specimens, La1-xSrxMnO3 (x = 0.2, 0.3, 0.4 and 0.5) have been fabricated and their dielectric spectra have been measured. The experimental results show that the dielectric relaxation processes of La1-x SrxMnO3 have near-Debye properties and their dielectric spectra can be fitted with well defined semicircles. In La1-xSrxMnO3, the dielectric relaxation results mainly from the trapped Mn-3d electron hopping via Mn3+-O-Mn4+; the hopping process can be described as a like-dipole torque. The near-Debye relaxation properties show that the interaction between like-dipole, Mn3+-O-Mn4+, is weak. With increasing Sr-dopant, when x<0.5, the dielectric loss peak frequency decreases however, when x>0.5, the dielectric loss peak frequency increases. (author)