Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
Phys Rev Lett. 2010 May 28;104(21):217003. doi: 10.1103/PhysRevLett.104.217003. Epub 2010 May 27.
The effect of disorder on the electronic properties near the Mott transition is studied in an organic superconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br, which is systematically irradiated by x rays. We observe that x ray irradiation causes Anderson-type electron localization due to molecular disorder. The resistivity at low temperatures demonstrates variable range hopping conduction with Coulomb interaction. The experimental results show clearly that the electron localization by disorder is enhanced by the Coulomb interaction near the Mott transition.
研究了无序对 Mott 转变附近电子性质的影响，在有机超导体 κ-(BEDT-TTF)2Cu[N(CN)2]Br 中，通过 x 射线对其进行系统照射。我们观察到 x 射线照射会由于分子无序而导致安德森型电子局域化。低温下的电阻率表现出具有库仑相互作用的可变范围跳跃传导。实验结果清楚地表明，在 Mott 转变附近，无序引起的电子局域化被库仑相互作用增强。
