Transport evidence of a magnetic quantum phase transition in electron-doped high-temperature superconductors

Abstract

We present magnetotransport evidence for antiferromagnetism in films of the electron-doped cuprates ${\mathrm{Pr}}_{2\ensuremath{-}x}{\mathrm{Ce}}_{x}\mathrm{Cu}{\mathrm{O}}_{4}$. Our results show clear signature of static or quasistatic antiferromagnetism up to optimal doping $x=0.15$, with a quantum phase transition close to $x=0.16$, and a coexistence of antiferromagnetism and superconductivity for $0.12\ensuremath{\leqslant}x\ensuremath{\leqslant}0.15$.