Quantum criticality

The interplay between magnetism and electronic correlations is a central tenant of condensed matter physics, where this interplay quite often results in the emergent phenomenon, such as unconventional superconductivity, non-Fermi-liquid behavior, or a quantum critical point (QCP). The magnetic QCP is a zero-temperature second order phase transition which is achieved by applying non-thermal control parameters, e.g., magnetic field, pressure, and chemical substitution, on a long-range magnetic ordered state. Near the QCP, quantum fluctuations dictate the underlying physics. Magnetic QCPs have been experimentally observed in many antiferromagnetic (AFM) systems. (Read more)