Speaker
Description
We compare the infrared responses of the underdoped cuprate superconductor YBa2Cu3O6.6 and the so-called telephone-number-compound Sr2Ca12Cu24O41. The charge carriers of the latter reside in layers of weakly coupled two-leg ladders.
The response of YBa2Cu3O6.6 was previously shown to exhibit a characteristic pseudogap and precursor superconducting pairing that develop well above Tc [1]. The infrared spectra of Sr2Ca12Cu24O41 reveal surprisingly similar features. A pseudogap appears here along the rungs and signatures of pair formation are seen along the legs of the ladders. This analogy provides evidence in favor of a stripe-like electronic structure of YBa2Cu3O6.6 and other high-Tc cuprates.
[1] A. Dubroka et al., Phys. Rev. Lett. 106, 047006 (2011).