Quantum destruction of stiffness in diluted antiferromagnets and superconductors

N. Bray-Ali; J. E. Moore

doi:10.1103/PhysRevB.69.184505

← Back to search

Quantum destruction of stiffness in diluted antiferromagnets and superconductors

N. Bray-Ali, J. E. Moore

DOI 10.1103/PhysRevB.69.184505 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

The reduction of two-dimensional (2D) superconducting or antiferromagnetic order by random dilution is studied as a model for the 2D diluted Heisenberg antiferromagnet La2Cu1−p(Zn,Mg)pO4 and randomly inhomogeneous 2D suerconductors. We show in simplified models that long-range order can persist at the percolation threshold despite the presence of disordered one-dimensional segments, contrary to the classical case. When long-range order persists to the percolation threshold, charging effects (in the superconductor) or frustrating interactions (in the antiferromagnet) can dramatically modify the stiffness of the order. This quantum destruction of stiffness is used to model neutron-scattering data on La2Cu1−p(Zn,Mg)pO4. In a certain simplified model, there is a sharp stiffness transition between “stiff” and “floppy” ordered phases.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
La2Cu1-p(Zn,Mg)pO4 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Bi2Sr2CaCu2O8 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown