Related papers: Topological Characters in Fe(Te$_{1-x}$Se$_x$) thi…
FeSe has been one of the most intensively studied iron-based superconductors over the past two decades, exhibiting a wide range of phenomena such as unconventional superconductivity, nematic order, magnetism, orbital-selective correlations,…
In a topological insulator (TI), if its spin-orbit coupling (SOC) strength is gradually reduced, the TI eventually transforms into a trivial insulator beyond a critical point of SOC, at which point the bulk gap closes: this is the standard…
To understand the chemical reaction at the interface of materials, we performed a transmission electron microscopy (TEM) observation in four types of Fe(Te,Se) superconducting thin films prepared on different types of substrates: CaF2…
The symmetry breaking induced by the ferroelectric transition often triggers the emergence of topological electronic states such as Weyl fermions in ferroelectric-like metals/semimetals. Such strong coupling between the lattice deformation…
The interplay of non-trivial band topology and magnetism gives rise to a series of exotic quantum phenomena, such as the emergent quantum anomalous Hall (QAH) effect and topological magnetoelectric effect. Many of these quantum phenomena…
We report transport studies of Mn-doped Bi2Te3 topological insulator (TI) films with accurately controlled thickness grown by molecular beam epitaxy. We find that films thicker than 5 quintuple-layer (QL) exhibit the usual anomalous Hall…
We use laser-based Angle-Resolved Photoemission Spectroscopy (ARPES) to study how chemical substitution modifies the electronic properties of the Bi2(Se{1-x}Tex)3 (BiSeTe) family of topological insulators. We find that increasing the Te…
The surface of a topological crystalline insulator (TCI) carries an even number of Dirac cones protected by crystalline symmetry. We epitaxially grew high quality Pb$_{1-x}$Sn$_x$Te(111) films and investigated the TCI phase by in-situ…
We use real-time reflection high energy electron diffraction intensity oscillation to establish the Te-rich growth dynamics of topological insulator thin films of Bi2Te3 on Si(111) substrate by molecular beam epitaxy. In situ angle resolved…
Pd$_3$Bi$_2$Se$_2$ is a rare realization of a superconducting metal with a non-zero $Z_2$ topological invariant. We report the growth of high-quality single crystals of layered Pd$_3$Bi$_2$Se$_2$ with a superconducting transition at $T_c$ ~…
We report a systematic study on the growth conditions of Sn$_{1-x}$In$_x$Te thin films by molecular beam epitaxy for maximization of superconducting transition temperature $T_\mathrm{c}$. Careful tuning of the flux ratios of Sn, In, and Te…
Topological phases have attracted much interest in recent years. While there are a number of three-dimensional materials exhibiting topological properties, there are relatively few two-dimensional examples aside from the well-known quantum…
The strong spin$-$orbit coupling (SOC) and numerous crystal phases in few$-$layer transition metal dichalcogenides (TMDCs) MX$_2$ (M$=$W, Mo, and X$=$Te, Se, S) has led to a variety of novel physics, such as Ising superconductivity and…
Superconducting iron chalcogenide FeSe has the simplest crystal structure among all the Fe-based superconductors. Unlike other iron pnictides, FeSe exhibits no long range magnetic order accompanying the tetragonal-to-orthorhombic structural…
By stacking PbTe layers there is a non-monotonic topological phase transition as a function of the number of monolayers. Based on first principles calculations we find that the proper stacked crystal symmetry determines the topological…
We report the structural, vibrational and electrical transport properties up to 16 GPa of the 1T-TiTe2, a prominent layered 2D system, which is predicted to show a series of topologically trivial - nontrivial transitions under hydrostatic…
Topological insulators (TI), with characteristic Dirac-fermion topological surface states (TSS), have emerged as a new class of electronic materials with rich potentials for both novel physics and device applications. However, a major…
We investigated the transport properties under magnetic fields of up to 9 T for FeSe$_{1-x}$Te$_x$ thin films on CaF$_2$. Measurements of the temperature dependence of the electrical resistivity revealed that for $x = 0.2 - 0.4$, where…
The iron-based superconductor FeTe$_{1-x}$Se$_{x}$ has attracted considerable attention as a candidate topological superconductor owing to a unique combination of topological surface states and bulk high-temperature superconductivity. The…
This study explores the emergence of superconductivity in high-quality ZrTe$_{2-x}$Se$_x$ crystals, grown via the isothermal chemical vapor transport (ICVT) technique. Resistive, structural, and thermal measurements reveal that substituting…