Pseudogap of optimally doped La1.85Sr0.15CuO4 observed by ultrahigh-resolution photoemission spectroscopy

Citation
T. Sato et al., Pseudogap of optimally doped La1.85Sr0.15CuO4 observed by ultrahigh-resolution photoemission spectroscopy, PHYS REV L, 83(11), 1999, pp. 2254-2257
Citations number
23
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
83
Issue
11
Year of publication
1999
Pages
2254 - 2257
Database
ISI
SICI code
0031-9007(19990913)83:11<2254:POODLO>2.0.ZU;2-I
Abstract
We have performed an ultrahigh-resolution (Delta E similar to 7 meV) photoe mission spectroscopy on La1.85Sr0.15CuO4 (T-c = 38 K) at 16-250 K. We found a pseudogap at E-F With the size of 30-35 meV, which is gradually filled i n by a transfer of states from the higher energy region with increasing tem perature, but persists over 200 K. The gap energy is consistent with the ch aracteristic temperatures of the magnetic susceptibility and the Hall coeff icient. The temperature evolution is well scaled with that of the Hall coef ficient. The pseudogap is not smoothly connected to the superconducting gap (Delta similar to 8 meV below T-c, suggesting a different origin from that in Bi2Sr2CaCu2O8.