Colossal Magnetoresistive p-n Junctions of Te-Doped LaMnO3/Nb-doped SrTiO3

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2003,（1）
• 页码范围: 137-140
• 页数: 4页
• 语种: 英文

摘要

We have fabricated colossal magnetoresistive (CMR) p-n junctions made of Te-doped LaMnOs and Nb-doped SrTiOa with laser molecular beam epitaxy. TheⅠ- Ⅴ characteristics of the Lao.aTeo.iMnOs/SrNfao.oiTio.ggOs p-n junctions as a function of applied magnetic field (0-5 T) were experimentally studied in the temperature range 77-300 K. The results indicate that the p-n junction exhibited the CMR behaviour. The magnetoresistance (MR) is positive at 220 K and 300 K, while it displays a negative MR at 77K. For a positive bias, the MR ratios (△R/RO, △R = RH - Ro) are 7.5% at 0.1 T and 18% at 5T for 300K, 5% at 0.1 T and 33% at 5T for 220K, -14% at 0.1 T and -71% at 5 T for 77K. For a negative bias, the MR ratios are 6.3% at 0.1 T and 10.8% at 3T for 300K, 5.1% at 0.1 T and 15% at 3T for 220K, -19% at 0.1 T and -72% at 5 T for 77K. The CMR behaviour of the p-n junction is different from those of the LaMnOa compound family.