Inelastic neutron scattering reveals a broad continuum of excitations in Pr_{2}Zr_{2}O_{7}, the temperature and magnetic field dependence of which indicate a continuous distribution of quenched transverse fields (Δ) acting on the non-Kramers Pr^{3+} 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)∝(Δ^{2}+Γ^{2})^{-1}, where Γ=0.27(1) meV. Established during high temperature synthesis due to an underlying structural instability, it appears disorder in Pr_{2}Zr_{2}O_{7} actually induces a quantum spin liquid.
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http://dx.doi.org/10.1103/PhysRevLett.118.107206 | DOI Listing |
ACS Nano
January 2025
John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.
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Uppsala University, Department of Physics and Astronomy, Box 516, SE-751 20 Uppsala, Sweden.
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December 2024
Flatiron Institute, Center for Computational Quantum Physics, New York, New York 10010, USA.
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Karlsruhe Institute of Technology, IQMT, 76131 Karlsruhe, Germany.
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RIKEN, Condensed Matter Theory Laboratory, CPR, Wako, Saitama 351-0198, Japan.
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