Polarization catastrophe in doped cuprates and metal-ammonia solutions. Metal-to-superconductor transition versus phase separation
Polarization catastrophe in doped cuprates and metal-ammonia solutions. Metal-to-superconductor transition versus phase separation
复制标题
掺杂铜酸盐和金属氨溶液中的极化灾难。
DOI：
10.1051/jp4:20020400
复制
发表时间：
2002
期刊：
影响因子：
--
通讯作者：
S. Fratini
中科院分区：
文献类型：
--
作者：
P. Quémerais;J. Raimbault;S. Fratini
在掺杂极性杂质时，例如铜酸盐（固体）或氨（液体），极化诱导极化子或溶剂化电子的形成。然而，这些实体在金属-绝缘体转变（MIT）中的确切作用仍然不清楚。我们认为，它们的形成以及它们的长程库仑相互作用是导致MIT的极化灾难的原因。此外，该振荡现象是静态介电常数的负号的出现，这可以产生在铜酸盐中的绝缘体到超导体的转变，或者在金属-氨溶液中的相分离。这种行为的差异可能来自于掺杂电荷的抗衡离子的性质，它们在氧化物中基本上是冻结的，而在金属-氨体系中则保持液态。
On doping polar dielectrics, such as cuprates (solid) or amonia (liquid), the polarization induces the formation of polarons or solvated electrons. However, the exact role of such entities in the metal-to-insulator transition (MIT) which occurs at some critical densities still remains unclear. We think that their formation together with their long-range Coulomb interactions are responsable for a polarization catastrophe leading to the MIT. Moreover, the accompanishing phenomena is the occurence of a negative sign of the static dielectric constant, which could yield either an insulator-to-superconductor transition in cuprates, either a phase separation in metal-ammonia solutions. The difference of behavior possibly could come from the nature of the counter ions of the doping charges, which are essentially frozen in oxides, while they remain in a liquid state in metal-ammonia system.