【摘要】 通过测量样品的M T曲线、M H曲线、ESR曲线、红外光谱、拉曼光谱、ρ -T曲线和MR T曲线 ,研究了双掺杂La0 .6 7+ 1 .33xSr0 .33- 1 .33xMn1 -xMgxO3(0.0 0≤x≤ 0 .2 5 )体系的磁电性质和输运行为。对x =0 .10和 0 .15 ,在温度高于TConset时出现相分离 ;对x =0 .2 0和 0 .2 5 ,在低温区出现了反铁磁 (AFM )行为。x =0 .0 5的 ρ-T关系存在金属 绝缘体 (MI)转变 ;x≥ 0 .15的所有样品在测量温区内显示绝缘体行为。这些奇异现象用M H关系、ESR曲线和拉曼光谱给予了很好的解释更多还原

【Abstract】 The magnetic and electric properties and transport behaviors of double doping La_0.67+1.33xSr_0.33-1.33xMn_1-xMg_xO₃ （0.00≤x≤0.25） were studied by measuring M-T curves, M-H curves, ESR curves, Infrared spectrum, Raman spectrum, ρ-T curves and MR-T curves. For x=0.10 and 0.15, there appears the phase separation at temperature higher than Tconset; for x=0.20 and 0.25, the AFM behavior is exhibited at lower temperature. For x=0.05, ρ-T curve exhibits MI transition associated; when x≥0.15, all the samples display insulating behavior in the temperature range measured. With the M-H relations and ESR spectra and Raman spectra, all above strange phenomena can be well explained.更多还原