Evidence of two-dimensional (2D) quantum critical fluctuations is observed in the superfluid density n s(T) λ -2(T) of extremely underdoped Bi 2Sr 2CaCu 2O 8+x (Bi-2212) films, indicating that, in general, quantum fluctuations play a dominant role in underdoped cuprates. Two-dimensional (2D) fluctuations are expressed by the linear scaling T c n s(0). 2D scaling in Bi-2212 contrasts with three-dimensional scaling that is seen in the much less anisotropic YBa 2Cu 3O 7-δ. Quantum critical fluctuations could also account for the absence of thermal critical behavior in λ -2(T) of strongly underdoped Bi-2212 samples, T c<48 K.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - 24 May 2012|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics