Related papers: Unconventional Fermi surface in an insulating stat…
The true topological nature of the Kondo insulator SmB$_6$ remains to be unveiled. Our previous tunneling study not only found evidence for the existence of surface Dirac fermions, but it also uncovered that they inherently interact with…
We report quantum oscillation measurements that enable the direct observation of the Fermi surface of the low temperature ground state of \ba122. From these measurements we characterize the low energy excitations, revealing that the Fermi…
Quantum oscillations are conventionally understood to arise from the Fermi level; hence, they are considered to be a proof of the existence of an underlying Fermi surface. In this article, we show that in certain situations quantum…
Topological insulators are emerging materials with insulating bulk and symmetry protected nontrivial surface states. One of the most fascinating transport behaviors in a topological insulator is the quantized anomalous Hall insulator, which…
A Kondo lattice is often electrically insulating at low temperatures. However, several recent experiments have detected signatures of bulk metallicity within this Kondo insulating phase. Here we visualize the real-space charge landscape…
Magnetic oscillations in strongly correlated insulating systems have garnered interest due to oscillations seemingly originating from the bulk, despite an anticipated gapped spectrum. We use the large-$N$ mean-field theory to study the…
Long known to have thermodynamic properties at odds with its insulating electrical transport, SmB6 has been the subject of great debate as it is unclear whether its unusual properties are related to the bulk or novel metallic surface…
Topological Kondo insulator SmB6 has attracted quite a lot of attentions from condensed matter physics community. A number of unique electronic properties, including low- temperature resistivity anomaly, 1D electronic transport and 2D Fermi…
One of the early triumphs of quantum physics is the explanation why some materials are metallic whereas others are insulating. While a treatment based on single electron states correctly predicts the character of most materials this…
We studied the electronic structure of SmB6 employing density functional theory (DFT) using different exchange potentials, spin-orbit coupling (SOC) and electron correlation (U = correlation strength). All the calculations carried out in…
4$f$ electron-based topological Kondo insulators have long been researched for their potential to conduct electric current via protected surface states, while simultaneously exhibiting unusually robust insulating behavior in their…
Samarium hexaboride crystallizes in a simple cubic structure (space group #221, Pm-3m), but its properties are far from being straightforward. Initially classified as a Kondo insulator born out of its intriguing intermediate valence ground…
Topological Kondo insulators are a new class of topological insulators in which metallic surface states protected by topological invariants reside in the bulk band gap at low temperatures. Unlike other three-dimensional topological…
The resurgence of interest in Kondo insulators has been driven by two major mysteries: the presence of metallic surface states and the observation of quantum oscillations. To further explore these mysteries, it is crucial to investigate…
In recent years, the study on the Kondo insulator SmB6, a strongly correlated electron material with decades-long puzzles, has become one of the most attractive topics again because the discovery of the coexistence of its unusual metallic…
The Kondo insulator compound SmB6 has emerged as a strong candidate for the realization of a topologically nontrivial state in a strongly correlated system, a topological Kondo insulator, which can be a novel platform for investigating the…
We measure the quantum capacitance and probe thus directly the electronic density of states of the high mobility, Dirac type of two-dimensional electron system, which forms on the surface of strained HgTe. Here we show that observed…
Recently there have been increasingly hot debates on whether a bulk Fermi surface of charge-neutral excitations exists in the topological Kondo insulator SmB6. To unambiguously resolve this issue, we performed the low-temperature thermal…
A synergistic effect between strong electron correlation and spin-orbit interaction (SOI) has been theoretically predicted to result in a new topological state of quantum matter on Kondo insulators (KIs), so-called topological Kondo…
We develop a theory of quantum oscillations in insulators with an emergent fermi sea of neutral fermions minimally coupled to an emergent $U(1)$ gauge field. As pointed out by Motrunich (Phys. Rev. B 73, 155115 (2006)), in the presence of a…