skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Disorder-Induced Quantum Spin Liquid in Spin Ice Pyrochlores

Authors:
;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1344819
Grant/Contract Number:
FG02-08ER46524
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 118; Journal Issue: 8; Related Information: CHORUS Timestamp: 2017-02-23 22:11:29; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Savary, Lucile, and Balents, Leon. Disorder-Induced Quantum Spin Liquid in Spin Ice Pyrochlores. United States: N. p., 2017. Web. doi:10.1103/PhysRevLett.118.087203.
Savary, Lucile, & Balents, Leon. Disorder-Induced Quantum Spin Liquid in Spin Ice Pyrochlores. United States. doi:10.1103/PhysRevLett.118.087203.
Savary, Lucile, and Balents, Leon. Thu . "Disorder-Induced Quantum Spin Liquid in Spin Ice Pyrochlores". United States. doi:10.1103/PhysRevLett.118.087203.
@article{osti_1344819,
title = {Disorder-Induced Quantum Spin Liquid in Spin Ice Pyrochlores},
author = {Savary, Lucile and Balents, Leon},
abstractNote = {},
doi = {10.1103/PhysRevLett.118.087203},
journal = {Physical Review Letters},
number = 8,
volume = 118,
place = {United States},
year = {Thu Feb 23 00:00:00 EST 2017},
month = {Thu Feb 23 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevLett.118.087203

Citation Metrics:
Cited by: 9works
Citation information provided by
Web of Science

Save / Share:
  • Solid-solutions of the "soft" quantum spin ice pyrochlore magnets Tb 2B 2O 7 with B=Ti and Sn display a novel magnetic ground state in the presence of strong B-site disorder, characterized by a low susceptibility and strong spin fluctuations to temperatures below 0.1 K. These materials have been studied using ac-susceptibility and muSR techniques to very low temperatures, and time-of-flight inelastic neutron scattering techniques to 1.5 K. Remarkably, neutron spectroscopy of the Tb 3+ crystal field levels appropriate to at high B-site mixing (0.5 < x < 1.5 in Tb 2Sn 2-xTi xO 7) reveal that the doublet ground andmore » first excited states present as continua in energy, while transitions to singlet excited states at higher energies simply interpolate between those of the end members of the solid solution. The resulting ground state suggests an extreme version of a random-anisotropy magnet, with many local moments and anisotropies, depending on the precise local configuration of the six B sites neighboring each magnetic Tb 3+ ion.« less
  • The pyrochlores in the series A{sub 2}Sb{sub 2}O{sub 7} have been synthesized and characterized as exhibiting spin glass transitions at T{sub SG}=41, 4.5, and 2.6 K (for A=Mn{sup 2+}S=5/2 , Co{sup 2+}S=3/2 and Ni{sup 2+}S=1, respectively) despite the lack of chemical disorder. Since the Curie-Weiss temperature remains essentially constant for all members in the series ({theta}{approx}-40K), the frustration index for these materials increases significantly as the moment size is reduced from f=|theta|/T{sub SG}=1.1 (Mn{sup 2+}), to 9.3 (Co{sup 2+}) to 14.6 (Ni{sup 2+}). There is also a corresponding change in the spin dynamics measured by the shift in the ACmore » susceptibility signal as a function of frequency. These new materials provide an avenue to investigate the effect of quantum fluctuations on the Heisenberg pyrochlore lattice in the low spin limit, and show there is a dramatic change in the spin dynamics as the quantum regime is approached. - A comparison of the spin glass ordering temperature, T{sub SG}, and the frustration index f as a function of the spin for the pyrochlore series A{sub 2}Sb{sub 2}O{sub 7}. In the limit of low spin, the frustration index increases by an order of magnitude.« less
  • The structure of Y{sub 2}(Zr{sub y}Ti{sub 1-y}){sub 2}O{sub 7} solid solutions progressively changes, with increasing y, from an ordered pyrochlore structure A{sub 2}B{sub 2}O{sub 7}{four_gradient}, space group Fd3m, to a deflect-fluorite structure (A,B){sub 4} (O{sub 0.875}{four_gradient}{sub 0.125}){sub 8}, space group Fm3m, at y = 0.90. The anion array consists of three independent sites O(1), O(2), and O(3), occupying positions 48f, 8a and 8b, respectively, of which 8b is unoccupied in a fully ordered pyrochlore. Rietveld powder-profile analysis of data collected with 1.5453-{angstrom} thermal neutrons was used to determine the structural state of four samples with increasing Zr content (y =more » 0.30, 0.45, 0.60, and 0.90). Refinements that employed only the pyrochlore superstructure intensity data provided weighted profile residuals that ranged 8.06 to 8.67% compared with expected values of 7.13 to 7.87% derived from counting statistics. The onset of disorder at y = 0.30 is marked by filling of the vacant 8b site with oxygen ions displaced from the nearest-neighbor anion shell - i.e., O(1) in 48f. Only for y > 0.45 does O(2) participate in the disorder. Mixing of the occupancy of cation sites A and B begins only with under occupancy of the O(2) site. The eight-coordinated A site, position 16c, is occupied solely by Y for y {le} 0.45 and is predominantly Y at y = 0.60. The substituted Zr{sup 4+} thus replaces Ti{sup 4+} in the six-coordinated B site for most of the solid-solution series. Complete mixing of all three cation species occurs abruptly over the narrow compositional range 0.60 < y {le} 0.90.« less
  • No abstract prepared.