Harnessing disorder to tune, tailor and design classical and quantum spin liquids
Lead Research Organisation:
University of Cambridge
Department Name: Physics
Abstract
Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.
Organisations
Publications
Chern L
(2022)
Competing quantum spin liquids, gauge fluctuations, and anisotropic interactions in a breathing pyrochlore lattice
in Physical Review B
De Tomasi G
(2022)
Effects of critical correlations on quantum percolation in two dimensions
in Physical Review B
Glittum C
(2023)
Emergence of quasiperiodic behavior in transport and hybridization properties of clean lattice systems
in Physical Review Research
Gray TH
(2022)
Enhanced diffusion in soft-walled channels with a periodically varying curvature.
in Physical review. E
Hallén JN
(2022)
Dynamical fractal and anomalous noise in a clean magnetic crystal.
in Science (New York, N.Y.)
Hart O
(2021)
Correlation holes and slow dynamics induced by fractional statistics in gapped quantum spin liquids.
in Nature communications
Hart O
(2020)
From compact localized states to many-body scars in the random quantum comb
in Physical Review Research
Hart O
(2021)
Logarithmic Entanglement Growth from Disorder-Free Localization in the Two-Leg Compass Ladder
in Physical Review Letters
Kelly N
(2022)
Magnetism on the stretched diamond lattice in lanthanide orthotantalates
in Physical Review Materials
Kelly N
(2022)
Crystal structure and specific heat of calcium lanthanide oxyborates Ca 4 Ln O(BO 3 ) 3
in Zeitschrift für Kristallographie - Crystalline Materials
Kim M
(2022)
Anderson localization of emergent quasiparticles: Spinon and vison interplay at finite temperature in a Z 2 gauge theory in three dimensions
in Physical Review Research
Koskelo E
(2023)
Comparative Study of Magnetocaloric Properties for Gd 3 + Compounds with Different Frustrated Lattice Geometries
in PRX Energy
Koskelo E
(2023)
Magnetic and Magnetocaloric Properties of the A 2 LnSbO 6 Lanthanide Oxides on the Frustrated fcc Lattice
in Inorganic Chemistry
Koskelo EC
(2022)
Free-Spin Dominated Magnetocaloric Effect in Dense Gd3+ Double Perovskites.
in Chemistry of materials : a publication of the American Chemical Society
Mustonen O
(2022)
Valence bond glass state in the 4d1 fcc antiferromagnet Ba2LuMoO6
in npj Quantum Materials
Pace SD
(2023)
Dynamical Axions in U(1) Quantum Spin Liquids.
in Physical review letters
Pearce MJ
(2022)
Magnetic monopole density and antiferromagnetic domain control in spin-ice iridates.
in Nature communications
Pughe C
(2022)
Site-Selective d10/d0 Substitution in an S = 1/2 Spin Ladder Ba2CuTe1-xWxO6 (0 = x = 0.3).
in Inorganic chemistry
Samarakoon A
(2022)
Structural magnetic glassiness in the spin ice Dy 2 Ti 2 O 7
in Physical Review Research
Samarakoon AM
(2022)
Anomalous magnetic noise in an imperfectly flat landscape in the topological magnet Dy2Ti2O7.
in Proceedings of the National Academy of Sciences of the United States of America
Stern M
(2021)
Quantum percolation of monopole paths and the response of quantum spin ice
in Physical Review B
Štrkalj A
(2022)
Coexistence of localization and transport in many-body two-dimensional Aubry-André models
in Physical Review B
| Description | (for the experimental part of the proposal, please see related reporting at RHUL and OXFORD) We gained a more in-depth understanding of the role of disorder in the form of oxygen deficiency in Ho-based pyrochlores. We characterised the effects at the microscopic, single-ion level. Characterisation of the macroscopic / collective behaviour is ongoing. We developed an understading of the nature of chemical composition disorder in Pr2ScNbO7. Comparison between theory and experiment allowed to understand the charge order / disorder in the distribution of Sc and Nb ions. This lead to crystallographic modelling and thence modelling of the magnetic properties of the Pr ions. Two different environments were identified, forming short quasi-1D chains. Preliminary results suggest that the one of the envoronments may be non-magnetic. Modelling of the resulting collective behaviour and furhter comparison with experiment is ongoing. Theoretical work on magnetic correlations in spin ice materials lead to the discovery of an emergent fractal in a clean system, which solves a long standing puzzle in the out of equilibrium behaviour and magnetic noise of these systems. |
| Exploitation Route | The discovery of the emergent fractal is a seminal result that is receiving much attention in the news. It is of interest to a broad range of scientific communities. Moreover, the idea of significant slowing down and temporal scaling behaviour in materials that does not originate from disorder but rather from internal correlations that mimic a percolation process may have important implications for people working on spin ice materials and out of equilibrum phenomena and glassiness in general. |
| Sectors | Education,Other |
| Title | Data associated with "Free-spin dominated magnetocaloric effect in dense Gd3+ double perovskites" |
| Description | Data associated with the publication 'Free-spin dominated magnetocaloric effect in dense Gd3+ double perovskites.' Frustrated lanthanide oxides with dense magnetic lattices are of fundamental interest for their potential in cryogenic refrigeration due to a large ground state entropy and suppressed ordering temperatures, but can often be limited by short-range correlations. Here, we present examples of frustrated fcc oxides, Ba2GdSbO6 and Sr2GdSbO6 and the new site-disordered analog Ca2GdSbO6 ([CaGd]A[CaSb]BO6), in which the magnetocaloric effect is influenced by minimal superexchange (J1 ~ 10 mK). We report on the crystal structures using powder x-ray diffraction and the bulk magnetic properties through low-field susceptibility and isothermal magnetization measurements. The Gd compounds exhibit a magnetic entropy change of up to -15.8 J/K/molGd in a field of 7 T at 2 K, a 20% excess compared to the value of -13.0 J/K/molGd for a standard in magnetic refrigeration, Gd3Ga5O12. Heat capacity measurements indicate a lack of magnetic ordering down to 0.4 K for Ba2GdSbO6 and Sr2GdSbO6, suggesting cooling down through the liquid 4-He regime. A mean-field model is used to elucidate the role of primarily free spin behavior in the magnetocaloric performance of these compounds in comparison to other top-performing Gd-based oxides. The chemical flexibility of the double perovskites raises the possibility of further enhancement of the magnetocaloric effect in the Gd3+ fcc lattices. Please see readme file for details on contents of folders |
| Type Of Material | Database/Collection of data |
| Year Produced | 2022 |
| Provided To Others? | Yes |
| URL | https://www.repository.cam.ac.uk/handle/1810/337073 |