Definitive Evidence for Order-by-Quantum-Disorder in Er2Ti2O7
| Autor: | Savary, Lucile, Ross, Kate A., Gaulin, Bruce D., Ruff, Jacob P. C., Balents, Leon |
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| Rok vydání: | 2012 |
| Předmět: | |
| Zdroj: | Phys. Rev. Lett. 109, 167201 (2012) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevLett.109.167201 |
| Popis: | Here we establish the systematic existence of a U(1) degeneracy of all symmetry-allowed Hamiltonians quadratic in the spins on the pyrochlore lattice, at the mean-field level. By extracting the Hamiltonian of Er2Ti2O7 from inelastic neutron scattering measurements, we then show that the U(1)-degenerate states of Er2Ti2O7 are its classical ground states, and unambiguously show that quantum fluctuations break the degeneracy in a way which is confirmed by experiment. This is the first definitive observation of order-by-disorder in any material. We provide further verifiable consequences of this phenomenon, and several additional comparisons between theory and experiment. Comment: 4.5 pages, 3 figures, 7.5 pages of Supplemental Material, 8 supplemental figures |
| Databáze: | arXiv |
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