Fig. 4: Concept of the reverse quantum limit.
From: The reverse quantum limit and its implications for unconventional quantum oscillations in YbB12
a Landau level diagram for the quantum limit (QL) and reverse quantum limit (RQL). Colors correspond to different Landau level indices and dashed/solid lines denote different spins. A conventional metal reaches the QL when the cyclotron energy exceeds the Fermi energy. An insulator with a Zeeman energy greater than the cyclotron energy is similar, except the Landau levels cross the chemical potential in reverse. b High-field electronic phase diagram considering if the electronic structure at the chemical potential is gapped (Δ > 0) or metallic (Δ < 0), and the strength of electronic correlations (\({g}^{*}\frac{{m}^{*}}{{m}_{{\rm {e}}}}\)).
