Scale-Invariant transport near quantum critical point in a cuprate superconductor

Thermodynamic measurements suggest the zero-temperature collapse of a line of classical phase transitions inside the superconducting dome in high-temperature superconductors. Together with the evidence for enhanced correlations near critical doping these measurements link the anomalous transport behavior near critical doping to quantum critical point inside the superconducting dome. Understanding the the physics of the anomalous relaxation dynamics in this "strange metal" state and elucidating the nature of its charge carriers is the next frontier. Our high-magnetic-filed measurements of electric transport in LSCO cuprates near critical doping (x=0.20) reveal linear-in-field resistivity at very high magnetic fields and a characteristic temperature-field competition observed at lower fields. Such scale-invariant behavior of magneto-transport suggests non-quasiparticle transport in the strange metal state.​