Year-end Sale % OFF 
Abstract
The breathing pyrochlore lattice material Ba3Yb2Zn5O11 exists in the nearly decoupled limit, in contrast to most other well-studied breathing pyrochlore compounds. As a result, it constitutes a useful platform to benchmark theoretical calculations of exchange interactions in insulating Yb3+ magnets. Here we study Ba3Yb2Zn5O11 at low temperatures in applied magnetic fields as a further probe of the physics of this model system. Experimentally, we consider the behavior of polycrystalline samples of Ba3Yb2Zn5O11 with a combination of inelastic neutron scattering and heat capacity measurements down to 75 mK and up to fields of 10 T. Consistent with previous work, inelastic neutron scattering finds a level crossing near 3 T, but no significant dispersion of the spin excitations is detected up to the highest applied fields. Refinement of the theoretical model previously determined at zero field can reproduce much of the inelastic neutron scattering spectra and specific heat data. A notable exception is a low temperature peak in the specific heat at ∼0.1 K. This may indicate the scale of interactions between tetrahedra or may reflect undetected disorder in Ba3Yb2Zn5O11.
Highlights
Breathing pyrochlore lattice materials have recently emerged as an interesting route to study various aspects of frustrated magnetism [1,2,3,4,5,6,7,8,9,10,11]
Specific heat measurements were performed on pelletized polycrystalline samples of Ba3Yb2Zn5O11 prepared as described in Ref. [5] using a 3He insert and a dilution refrigerator insert, in a Quantum Design Physical Property Measurement System (PPMS)
The measurements presented here have a minimum temperature of 75 mK, this feature likely corresponds to the peak at ∼ 63 mK observed by Ref. [7] as no additional upturn is observed in the data presented here as would be expected if the feature at ∼ 63 mK was to be manifest in our measurements down to this temperature
Summary
Breathing pyrochlore lattice materials have recently emerged as an interesting route to study various aspects of frustrated magnetism [1,2,3,4,5,6,7,8,9,10,11]. The breathing pyrochlore lattice consists of a three dimensional network of corner sharing tetrahedra which alternate in size between large and small (see Fig. 1). By tuning the relative importance of these interactions, one can tune between decoupled tetrahedra and the full pyrochlore lattice. Known examples of breathing pyrochlore materials have been found to lie at the extremes of these behaviors, realizing either near equal couplings [1, 2, 9, 11], or having weakly coupled, nearly non-interacting tetrahedra [4]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
