Kondo T, Khasanov R, Karpinski J, Kazakov S M, Zhigadlo N D, Ohta T, Fretwell H M, Palczewski A D, Koll J D, Mesot J, Rotenberg E, Keller H, Kaminski A
Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
Phys Rev Lett. 2007 Apr 13;98(15):157002. doi: 10.1103/PhysRevLett.98.157002. Epub 2007 Apr 11.
We use microprobe angle-resolved photoemission spectroscopy (microARPES) to separately investigate the electronic properties of CuO2 planes and CuO chains in the high temperature superconductor, YBa2Cu4O8. For the CuO2 planes, a two-dimensional (2D) electronic structure is observed and, in contrast to Bi2Sr2CaCu2O8+delta, the bilayer splitting is almost isotropic and 50% larger, which strongly suggests that bilayer splitting has no direct effect on the superconducting properties. In addition, the scattering rate for the bonding band is about 1.5 times stronger than the antibonding band and is independent of momentum. For the CuO chains, the electronic structure is quasi-one-dimensional and consists of a conduction and insulating band. Finally, we find that the conduction electrons are well confined within the planes and chains with a nontrivial hybridization.
我们使用微探针角分辨光电子能谱（microARPES）分别研究高温超导体YBa2Cu4O8中CuO2平面和CuO链的电子性质。对于CuO2平面，观察到二维（2D）电子结构，并且与Bi2Sr2CaCu2O8+δ相比，双层分裂几乎是各向同性的，且大50%，这强烈表明双层分裂对超导性质没有直接影响。此外，成键带的散射率比反键带强约1.5倍，且与动量无关。对于CuO链，电子结构为准一维，由一个导带和一个绝缘带组成。最后，我们发现传导电子通过非平凡杂化很好地限制在平面和链内。
