Quantum critical behavior of the charge-density-wave in Fe-doped BaNi<sub>2</sub>As<sub>2</sub>
ORAL
Abstract
BaNi2As2 has recently received considerable attention due to unconventional charge density wave (CDW) transitions, a proposed nematic-liquid state, as well as nematicity and/or soft phonon strongly enhanced superconductivity [1-8]. Here we investigate Fe-doped BaNi2As2 using various thermodynamic and transport probes. In contrast to P- and Sr-substituted BaNi2As2 , the suppression of the CDWs occurs smoothly to zero temperature, terminating at a second-order quantum phase transition (QPT). We find anomalously large, and sign-changing, phonon Grüneisen parameters at this QPT, suggestive of a novel CDW/structural quantum phase transition.
[1] K. Kudo et al., PRL 109, 097002 (2012).
[2] C. Eckberg, et al., Nat. Phys. 16, 346 (2020).
[3] M. Merz, et al., PRB 104, 184509 (2021).
[4] Y. Yao, et al., Nat. Commun. 13, 4535 (2022).
[5] S. M. Souliou, et al., arXiv:2207.07191.
[6] Y. Song, et al., arXiv:2207.03289.
[7] M. Frachet, et al., arXiv:2207.02462.
[8] C. Meingast, et al. arXiv:2207.02294.
[1] K. Kudo et al., PRL 109, 097002 (2012).
[2] C. Eckberg, et al., Nat. Phys. 16, 346 (2020).
[3] M. Merz, et al., PRB 104, 184509 (2021).
[4] Y. Yao, et al., Nat. Commun. 13, 4535 (2022).
[5] S. M. Souliou, et al., arXiv:2207.07191.
[6] Y. Song, et al., arXiv:2207.03289.
[7] M. Frachet, et al., arXiv:2207.02462.
[8] C. Meingast, et al. arXiv:2207.02294.
*Work at KIT was partially funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Founda- tion) - TRR 288-422213477 (project A02).
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Presenters
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Christoph Meingast
- IQMT, Karlsruhe Institute of Technology, Germany
- Karlsruhe Institute of Technology