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We present a comprehensive study of the inhomogeneous mixed-valence compound, EuPd3S4, by electrical transport, X-ray diffraction, time-domain151Eu synchrotron Mössbauer spectroscopy, and X-ray absorption spectroscopy measurements under high pressure. Electrical transport measurements show that the antiferromagnetic ordering temperature,TN, increases rapidly from 2.8 K at ambient pressure to 23.5 K at ~19 GPa and plateaus between ~19 and ~29 GPa after which no anomaly associated withTNis detected. A pressure-induced first-order structural transition from cubic to tetragonal is observed, with a rather broad coexistence region (~20 GPa to ~30 GPa) that corresponds to theTNplateau. Mössbauer spectroscopy measurements show a clear valence transition from approximately 50:50 Eu2+:Eu3+to fully Eu3+at ~28 GPa, consistent with the vanishing of the magnetic order at the same pressure. X-ray absorption data show a transition to a fully trivalent state at a similar pressure. Our results show that pressure first greatly enhancesTN, most likely via enhanced hybridization between the Eu 4fstates and the conduction band, and then, second, causes a structural phase transition that coincides with the conversion of the europium to a fully trivalent state.
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Perturbation-tuned triple spiral metamagnetism and tricritical point in kagome metal ErMn6Sn6
Abstract Kagome materials are of topical interest for their diverse quantum properties linked with correlated magnetism and topology. Here, we report anomalous hydrostatic pressure (p) effect on ErMn6Sn6through isobaric and isothermal-isobaric magnetization measurements. Magnetic field (H) suppresses antiferromagneticTNwhile simultaneously enhancing the ferrimagneticTCby exhibiting dual metamagnetic transitions, arising from the triple-spiral-nature of Er and Mn spins. Counter-intuitively, pressure enhances bothTCandTNwith a growth rate of 74.4 K GPa−1and 14.4 K GPa−1respectively. Pressure unifies the dual metamagnetic transitions as illustrated throughp-Hphase diagrams at 140 and 200 K. Temperature-field-pressure (T-H,T-p) phase diagrams illustrate distinct field- and pressure-induced critical points at (Tcr= 246 K,Hcr= 23.3 kOe) and (Tcr= 435.8 K,pcr= 4.74 GPa) respectively. An unusual increase of magnetic entropy by pressure aroundTcrand a putative pressure-induced tricritical point pave a unique way of tuning the magnetic properties of kagome magnets through simultaneous application ofHandp.
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- PAR ID:
- 10625350
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Communications Materials
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2662-4443
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s43246-024-00552-x
