Electronic correlations and topology in 5f-electron Kondo insulators

Topological Kondo insulators have garnered significant interest in the realm of strongly correlated electronic systems. Special interest has been devoted to samarium hexaboride (SmB₆), which has been proposed to be the first member of such family. Recent advancements, utilizing a combination of dynamical mean field theory and density functional theory, have theoretically proposed its Pu analogue, PuB₆, as an intermediate valent, strongly correlated topological insulator characterized by nontrivial Z₂ topological invariants and metallic surface states (X. Deng et al., Phys. Rev. Lett. 111, 176404 (2013)). Here, we demonstrate, by low-temperature magneto-transport studies and DFT+U calculations, that PuB₆ shows features of topological Kondo insulating state. The topological nature of PuB₆ is further supported by the theoretical calculations, where we show that GGA+U is capable to properly capture electronic, topological, and lattice properties of PuB₆ with much lower computational cost than DMFT.