Inelastic neutron scattering reveals a broad continuum of excitations in Pr2Zr2O7, the temperature and magnetic field dependence of which indicate a continuous distribution of quenched transverse fields (Δ) acting on the non-Kramers Pr3+ crystal field ground state doublets. Spin-ice correlations are apparent within 0.2 meV of the Zeeman energy. A random phase approximation provides an excellent account of the data with a transverse field distribution ρ(Δ)∝(Δ2+Γ2)−1 where Γ=0.27(1) meV. Established during high temperature synthesis due to an underlying structural instability, it appears disorder in Pr2Zr2O7 actually induces a quantum spin liquid.
@article{arxiv.1609.08551,
title = {Disordered Route to the Coulomb Quantum Spin Liquid: Random Transverse Fields on Spin Ice in Pr$_2$Zr$_2$O$_7$},
author = {J. -J. Wen and S. M. Koohpayeh and K. A. Ross and B. A. Trump and T. M. McQueen and K. Kimura and S. Nakatsuji and Y. Qiu and D. M. Pajerowski and J. R. D. Copley and C. L. Broholm},
journal= {arXiv preprint arXiv:1609.08551},
year = {2017}
}