Quantum critical scaling and superconductivity in heavy electron materials

Abstract

We use the two fluid model to determine the conditions under which the nuclear spin-lattice lattice relaxation rate T1 of candidate heavy quantum critical superconductors can exhibit scaling behavior and find that it can occur if and only if their “hidden” quantum critical spin fluctuations give rise to a temperature-independent intrinsic heavy electron spin-lattice relaxation rate. The resulting scaling of T1 with the strength of the heavy electron component and the coherence temperature T* provides a simple test for their presence at pressures at which the superconducting transition temperature Tc is maximum and is proportional to T*. These findings support the previously noted partial scaling of the spin-lattice relaxation rate with Tc in a number of important heavy electron materials and provide additional evidence that in these materials their optimal superconductivity originates in the quantum critical spin fluctuations associated with a nearby phase transition from partially localized to fully itinerant quasiparticles.

Source-reported materials — not catalogue approval

Similar papers