title: Evidence for a transition in the pairing symmetry of the electron-doped cuprates La(2-x)Ce(x)CuO(4-y) and Pr(2-x)Ce(x)CuO(4-y).
abstract: We present measurements of the magnetic penetration depth, lambda(-2)(T), in Pr(2-x)Ce(x)CuO(4-y) and La(2-x)Ce(x)CuO(4-y) films at three Ce doping levels, x, near optimal. Optimal and overdoped films are qualitatively and quantitatively different from underdoped films. For example, lambda(-2)(0) decreases rapidly with underdoping but is roughly constant above optimal doping. Also, lambda(-2)(T) at low T is exponential at optimal and overdoping but is quadratic at underdoping. In light of other studies that suggest both d- and s-wave pairing symmetry in nominal optimally doped samples, our results are evidence for a transition from d- to s-wave pairing near optimal doping.
authors: Department of Physics, The Ohio State University, Columbus, Ohio 43210-1106, USA.
authors: John A
authors: JA
authors: Skinta
authors: Mun-Seog
authors: MS
authors: Kim
authors: Thomas R
authors: TR
authors: Lemberger
authors: T
authors: T
authors: Greibe
authors: M
authors: M
authors: Naito