Related papers: Record Surface State Mobility and Quantum Hall Eff…
Electrical field control of the carrier density of topological insulators (TI) has greatly expanded the possible practical use of these materials. However, the combination of low temperature local probe studies and a gate tunable TI device…
Ultrathin topological insulator membranes are building blocks of exotic quantum matter. However, traditional epitaxy of these materials does not facilitate stacking in arbitrary orders, while mechanical exfoliation from bulk crystals is…
Combining the ability to prepare high-quality, intrinsic Bi$_2$Te$_3$ topological insulator thin films of low carrier density with in-situ protective capping, we demonstrate a pronounced, gate-tunable change in transport properties of…
We consider a thin film of a topological insulator (TI) sandwiched between two ferromagnetic (FM) layers. The system is additionally under an external gate voltage. The surface electron states of TI are magnetized due to the magnetic…
A key feature of the topological surface state under a magnetic field is the presence of the zeroth Landau level at the zero energy. Nonetheless, it has been challenging to probe the zeroth Landau level due to large electron-hole puddles…
In ideal topological insulator (TI) films the bulk state, which is supposed to be insulating, should not provide any electric coupling between the two metallic surfaces. However, transport studies on existing TI films show that the…
Based on a combination of $k \cdot p$ theory, band topology analysis and electronic structure calculations, we predict the (111) thin films of the SnTe class of three-dimensional (3D) topological crystalline insulators realize the quantum…
We measured the response of the surface state spectrum of epitaxial Sb2Te3 thin films to applied gate electric fields by low temperature scanning tunneling microscopy. The gate dependent shift of the Fermi level and the screening effect…
Topological insulators (TIs) constitute a new class of materials with unique properties resulting from the relativistic-like character and topological protection of their surface states. Theory predicts these to exhibit a rich variety of…
The quantum anomalous Hall (QAH) state is a two-dimensional bulk insulator with a non-zero Chern number in absence of external magnetic fields. Protected gapless chiral edge states enable dissipationless current transport in electronic…
Topological insulators (TIs) are predicted to be composed of an insulating bulk state along with conducting channels on the boundary of the material. In Bi2Se3, however, the Fermi level naturally resides in the conduction band due to…
The Hall effect, the anomalous Hall effect and the spin Hall effect are fundamental transport processes in solids arising from the Lorentz force and the spin-orbit coupling respectively. The quantum versions of the Hall effect and the spin…
We demonstrate evidences of electronic transport via topological Dirac surface states in a thin film of strained HgTe. At high perpendicular magnetic fields, we show that the electron transport reaches the quantum Hall regime with vanishing…
The quantum anomalous Hall (QAH) effect has recently been realized in thin films of intrinsic magnetic topological insulators (IMTIs) like MnBi$_2$Te$_4$. Here we point out that that the QAH gaps of these IMTIs can be optimized, and that…
Magnetic devices are a leading contender for implementing memory and logic technologies that are nonvolatile, that can scale to high density and high speed, and that do not suffer wear-out. However, widespread applications of magnetic…
A topological insulator (TI), a new quantum state featured with the topologically-protected surface state (TSS) originating from its peculiar topology in band structure, has attracted much interest due to academic and practical importance.…
Three-dimensional (3D) topological insulators (TI) are novel quantum materials with insulating bulk and topologically protected metallic surfaces with Dirac-like band structure. The spin-helical Dirac surface states are expected to host…
Recently, the development of efficient and non-noble metal electrocatalysts with excellent durability for the hydrogen evolution reaction (HER) has attracted increasing attention. The exotic and robust metallic surface states of topological…
Topological insulators (TIs) are exotic materials which have topologically protected states on the surface due to the strong spin-orbit coupling. However, a lack of ordered growth of TI thin films on amorphous dielectrics and/or insulators…
While evidence of a topologically nontrivial surface state has been identified in surface-sensitive measurements of Bi2Se3, a significant experimental concern is that no signatures have been observed in bulk transport. In a search for such…