Abstract
The quantum limit in a Fermi liquid, realized when a single Landau level is occupied in strong magnetic fields, gives rise to unconventional states, including the fractional quantum Hall effect and excitonic insulators. Stronger interactions in metals with nearly localized f-electron degrees of freedom increase the likelihood of these unconventional states. However, access to the quantum limit is typically impeded by the tendency of f-electrons to polarize in a strong magnetic field, consequently weakening the interactions. In this study, we propose that the quantum limit in such systems must be approached in reverse, starting from an insulating state at zero magnetic field. In this scenario, Landau levels fill in the reverse order compared to regular metals and are closely linked to a field-induced insulator-to-metal transition. We identify YbB12 as a prime candidate for observing this effect and propose the presence of an excitonic insulator state near this transition.
| Original language | English |
|---|---|
| Article number | 1607 |
| Journal | Nature Communications |
| Volume | 15 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2024 |
| Externally published | Yes |
Funding
This work was supported by the Department of Energy (DOE) Basic Energy Sciences (BES) project “Science of 100 Tesla.” The National High Magnetic Field Laboratory is funded by National Science Foundation (NSF) Cooperative Agreements No. DMR-1157490 and No. 1164477, the State of Florida, and DOE. C.A.M. and M.K.C. were supported by the LANL LDRD Program, Project No. 20210320ER. M.K.C. acknowledges support from the NSF IR/D program while serving at the National Science Foundation. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. S.K.K. acknowledges support of the LANL Directors Postdoctoral Funding LDRD program. This work made use of the synthesis facility of the Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM), which is supported by the NSF under Cooperative Agreement No. DMR-2039380. Work by the Institute for Quantum Matter, an Energy Frontier Research Center, was funded by DOE, Office of Science, BES under Award No. DE-SC0019331. The authors thank Joe D. Thompson for performing the susceptibility measurements in the and Boris Maiorov for helpful discussions.