Abstract
In this work, we present our discovery and characterization of a new kagome prototype structure, KV3Sb5. We also present the discovery of the isostructural compounds RbV3Sb5 and CsV3Sb5. All materials exhibit a structurally perfect two-dimensional kagome net of vanadium. Density-functional theory calculations indicate that the materials are metallic, with the Fermi level in close proximity to several Dirac points. Powder and single-crystal syntheses are presented, with postsynthetic treatments shown to deintercalate potassium from single crystals of KV3Sb5. Considering the proximity to Dirac points, deintercalation provides a convenient means to tune the Fermi level. Magnetization measurements indicate that KV3Sb5 exhibits behavior consistent with a the Curie-Weiss model at high temperatures, although the effective moment is low (0.22μB per vanadium ion). An anomaly is observed in both magnetization and heat capacity measurements at 80 K, below which the moment is largely quenched. Elastic neutron scattering measurements find no obvious evidence of long-range or short-range magnetic ordering below 80 K. The possibility of an orbital-ordering event is considered. Single-crystal resistivity measurements show the effect of deintercalation on the electron transport and allow estimation of the Kadowaki-Woods ratio in KV3Sb5. We find that A/γ2∼61μOhm cm molFU2K2J-2, suggesting that correlated electron transport may be possible. KV3Sb5 and its cogeners RbV3Sb5 and CsV3Sb5 represent a new family of kagome metals, and our results demonstrate that they deserve further study as potential model systems.
| Original language | English |
|---|---|
| Article number | 094407 |
| Journal | Physical Review Materials |
| Volume | 3 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 16 2019 |
| Externally published | Yes |
Funding
B.R.O. and E.S.T. acknowledge support from the National Science Foundation, Grant No. 1729594. B.R.O. also acknowledges support from the California NanoSystems Institute through the Elings Fellowship program. L.C.G. and E.E. acknowledge support from the National Science Foundation, Grants No. 1729149 and No. 1437106. J.R.M. and M.W. acknowledge support from the Institute for Quantum Matter, U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award No. DE-SC0019331. T.M.M. acknowledges the David and Lucile Packard Foundation, and the Johns Hopkins University Catalyst Award. J.R.N. and I.W.H.O. acknowledge support from the A.P. Sloan Foundation. E.S.T., J.R.N., and I.W.H.O. acknowledge the Research Corporation for Science Advancement through Cottrell Scholar Awards. S.D.W. and M.B acknowledge support from 538 DOE, Office of Science, Basic Energy Sciences under Award No. DE-SC0017752. M.B. also acknowledges support from the National Science Foundation Graduate Research Fellowship Program, Grant No. 1650114. M.W. was supported by the Foundation for Polish Science (FNP). The research reported here made use of shared facilities of the UCSB MRSEC (NSF DMR 1720256). Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Access to MACS was provided by the Center for High Resolution Neutron Scattering, a partnership between the National Institute of Standards and Technology and the National Science Foundation under Agreement No. DMR-1508249. We thank Paul Sarte for the helpful discussion. B.R.O. and E.S.T. acknowledge support from the National Science Foundation, Grant No. 1729594. B.R.O. also acknowledges support from the California Nano Systems Institute through the Elings Fellowship program. L.C.G. and E.E. acknowledge support from the National Science Foundation, Grants No. 1729149 and No. 1437106. J.R.M. and M.W. acknowledge support from the Institute for Quantum Matter, U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award No. DE-SC0019331. T.M.M. acknowledges the David and Lucile Packard Foundation, and the Johns Hopkins University Catalyst Award. J.R.N. and I.W.H.O. acknowledge support from the A.P. Sloan Foundation. E.S.T., J.R.N., and I.W.H.O. acknowledge the Research Corporation for Science Advancement through Cottrell Scholar Awards. S.D.W. and M.B acknowledge support from 538 DOE, Office of Science, Basic Energy Sciences under Award No. DE-SC0017752. M.B. also acknowledges support from the National Science Foundation Graduate Research Fellowship Program, Grant No. 1650114. M.W. was supported by the Foundation for Polish Science (FNP). The research reported here made use of shared facilities of the UCSB MRSEC (NSF DMR 1720256). Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Access to MACS was provided by the Center for High Resolution Neutron Scattering, a partnership between the National Institute of Standards and Technology and the National Science Foundation under Agreement No. DMR-1508249. We thank Paul Sarte for the helpful discussion.
| Funders | Funder number |
|---|---|
| A.P. Sloan Foundation | |
| California Nano Systems Institute | |
| California NanoSystems Institute | 1437106 |
| Center for High Resolution Neutron Scattering | |
| Institute for Quantum Matter | |
| Office of Basic Energy Sciences | DE-SC0019331 |
| UCSB MRSEC | NSF DMR 1720256 |
| National Science Foundation | 1729594, 1729149 |
| David and Lucile Packard Foundation | |
| U.S. Department of Energy | |
| National Institute of Standards and Technology | DMR-1508249 |
| Research Corporation for Science Advancement | |
| Office of Science | |
| Basic Energy Sciences | DE-SC0017752, 1650114 |
| Argonne National Laboratory | DE-AC02-06CH11357 |
| Johns Hopkins University | |
| Fundacja na rzecz Nauki Polskiej |