Divergence of the quasiparticle lifetime with doping and evidence for pre-formed pairs below T* in YBa_2Cu3$O_{7-δ}
| dc.creator | Mihailovic, D. | |
| dc.creator | Podobnik, B. | |
| dc.creator | Demsar, J. | |
| dc.creator | Wagner, G. | |
| dc.creator | Evetts, J. | |
| dc.date | 1998-01-07 | |
| dc.date.accessioned | 2026-07-07T03:09:45Z | |
| dc.date.available | 2026-07-07T03:09:45Z | |
| dc.description | We report new time-resolved data of quasiparticle relaxation and Cooper pair recombination dynamics in YBa_2Cu_3O_{7-δ}, measured as a function of temperature and doping δusing femtosecond optical spectroscopy. The data show the existence of a normal state pseudo-gap for in-plane charge excitations below T* and an unusual divergence of the quasiparticle relaxation time in the superconducting state τ_s with δtowards optimum doping. In the underdoped state, no change in the amplitude of the induced transmission (which is proportional to the DOS at E_F), or relaxation time τ_s is observed at T_c. From the sum rule, both observations signify that no gap opens at T_c in underdoped YBCO for δ>0.15. T_c in this case only signifies the onset of phase coherence. The presented data thus suggest pair formation with an associated redistribution of the DOS starting at T* and the establishment of phase coherence at T_c consistent with Bose-Einstein condensation. In the optimally doped material, δ~ 0.1, on the other hand, both a divergence in lifetime and a change of the DOS occur at T_c, signifying the opening of a gap and the occurence of pairing takes place simultaneously. | |
| dc.description | 5 pages, 4 figures | |
| dc.identifier | https://arxiv.org/abs/cond-mat/9801049 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/9801049 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/28006 | |
| dc.subject | Superconductivity | |
| dc.subject | Strongly Correlated Electrons | |
| dc.title | Divergence of the quasiparticle lifetime with doping and evidence for pre-formed pairs below T* in YBa_2Cu3$O_{7-δ} | |
| dc.type | text |