Hole Localization in Underdoped Superconducting Cuprates Near 1/8th Doping
Abstract
Measurements of thermal conductivity versus temperature over a broad range of doping in YBa
2
Cu
3
O
6+x
and HgBa
2
Ca
n−1
Cu
n
O
2n+2+δ
(
n
=1,2,3) suggest that small domains of localized holes develop for hole concentrations near
p
=1/8. The data imply a mechanism for localization that is intrinsic to the CuO
2
-planes and is enhanced via pinning associated with oxygen-vacancy clusters.