Sources of quantum protection in high-T(c) superconductivity
The layer-structure cuprates with high superconducting transition temperatures T(c) exhibit a number of anomalous electronic properties in both superconducting and normal states. These anomalies are ascribed to the existence of independent spectra of excitations for charge and for spin, signaling a collective state, a "quantum protectorate."
Anderson
PW
Joseph Henry Laboratories of Physics, Princeton University, Princeton, NJ 08544, USA. E-mail: pwa@pupgg.princeton.edu.