Related papers: Using nonlocal surface transport to identify the a…
Recent progress in the field of topological states of matter(1,2) has largely been initiated by the discovery of bismuth and antimony chalcogenide bulk topological insulators (TIs)(3-6), followed by closely related ternary compounds(7-16)…
Several small-bandgap semiconductors are now known to have protected metallic surface states as a consequence of the topology of the bulk electron wavefunctions. The known "topological insulators" with this behavior include the important…
We predict by first-principles calculations that thin films of Cr-doped (Bi,Sb)$_2$Te$_3$ magnetic topological insulator have gapless non-chiral edge states coexisting with the chiral edge state. Such gapless non-chiral states are not…
The surface states of a 3D topological insulator (TI) exhibit topological protection against backscattering. However, the contribution of bulk electrons to the transport data is an impediment to the topological protection of surface. We…
The strong topological insulator in 3D is expected to realize a quantized magneto-electric response, the so-called axion response. However, many of the materials predicted to be topological insulators have turned out to be metallic, with…
We propose SnBi2Te4 to be a novel candidate material exhibiting temperature (T) mediated transitions between rich topological phases. From a combined theoretical and experimental studies, we find that SnBi2Te4 goes from a low-T topological…
I analyze electron transport through a Y-junction formed by helical edge states of a two-dimensional topological insulator (2DTI), focusing on the strongly interacting regime. An experimentally motivated device geometry and a…
Ultra-clean graphene sheets encapsulated between hexagonal boron nitride crystals host two-dimensional electron systems in which low-temperature transport is solely limited by the sample size. We revisit the theoretical problem of carrying…
Nanowires (NWs) of topological materials are emerging as an exciting platform to probe and engineer new quantum phenomena that are hard to access in bulk phase. Their quasi-one-dimensional geometry and large surface-to-bulk ratio unlock new…
This article reviews recent theoretical and experimental work on transport due to the surface states of three-dimensional topological insulators. The theoretical focus is on longitudinal transport in the presence of an electric field,…
To harness the true potential of topological insulators as quantum materials for information processing, it is imperative to maximise topological surface state conduction, while simulateneously improving their quantum coherence. However,…
We examine nonlocal conductivity in high-temperature superconductors from a phenomenological point of view. One wants to deduce the properties of the conductivity, especially its inherent length scales, from the transport data. Although…
The magnetic properties of the van der Waals magnetic topological insulators MnBi$_2$Te$_4$ and MnBi$_4$Te$_7$ are investigated by magneto-transport measurements. We evidence that the relative strength of the inter-layer exchange coupling J…
Topological insulator (TI) materials such as Bi2Te3 and Bi2Se3 have attracted strong recent interests. Large scale, high quality TI thin films are important for developing TI-based device applications. In this work, structural and…
We propose that half-quantized helical hinge currents manifest as the fingerprint of the axion insulator (AI). These helical hinge currents microscopically originate from the lateral Goos-H\"anchen (GH) shift of massless side-surface Dirac…
By employing angle-resolved photoemission spectroscopy combined with first-principles calculations, we performed a systematic investigation on the electronic structure of LaBi, which exhibits extremely large magnetoresistance (XMR), and is…
Single-crystalline \beta-Ag2Se nanostructures, a new class of 3D topological insulators (TIs), were synthesized using the chemical vapor transport method. The topological surface states were verified by measuring electronic transport…
Topological quantum materials coupled with magnetism can provide a platform for realizing rich exotic physical phenomena, including quantum anomalous Hall effect, axion electrodynamics and Majorana fermions. However, these unusual effects…
KZnBi was discovered recently as a new three-dimensional Dirac semimetal with a pair of bulk Dirac fermions in contrast to the $\mathbb{Z}_2$ trivial insulator reported earlier. In order to address this discrepancy, we have performed…
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…