相关论文: Ambipolar transport in bulk crystals of a topologi…
Achieving true bulk insulating behavior in Bi$_2$Se$_3$, the archetypal topological insulator with a simplistic one-band electronic structure and sizable band gap, has been prohibited by a well-known self-doping effect caused by selenium…
Topological insulators represent a new state of quantum matter attractive to both fundamental physics and technological applications such as spintronics and quantum information processing. In a topological insulator, the bulk energy gap is…
Topological insulators are known to their metallic surface states, a result of strong-spin-orbital coupling, that show unique surface transport phenomenon. But these surface transports are buried in presence of metallic bulk conduction. We…
Electronic transport experiments involving the topologically protected states found at the surface of Bi2Se3 and other topological insulators require fine control over carrier density, which is challenging with existing bulk-doped material.…
Topological insulators (TIs) are new insulating materials with exotic surface states, where the motion of charge carriers is described by the Dirac equations and their spins are locked in a perpendicular direction to their momentum. Recent…
We report a transport study of exfoliated few monolayer crystals of topological insulator Bi$_2$Se$_3$ in an electric field effect (EFE) geometry. By doping the bulk crystals with Ca, we are able to fabricate devices with sufficiently low…
Superconductivity (SC) in the Ba-122 family of iron-based compounds can be controlled by aliovalent or isovalent substitutions, applied external pressure, and strain, the combined effects of which are sometimes studied within the same…
Topological insulators (TIs) have attracted much attention due to their spin-polarized surface and edge states, whose origin in symmetry gives them intriguing quantum-mechanical properties. Robust control over the chemical potential of TI…
We report experimental evidence of surface dominated transport in single crystalline nanoflake devices of topological insulator Bi1.5Sb0.5Te1.8Se1.2. The resistivity measurements show dramatic difference between the nanoflake devices and…
Topological insulators are predicted to present novel surface transport phenomena, but their experimental studies have been hindered by a metallic bulk conduction that overwhelms the surface transport. We show that a new topological…
We present a study of the structural and electronic properties of highly doped topological insulator Bi2Se3 single crystals synthesized by the Bridgman method. Lattice structural characterizations by X-ray diffraction, scanning tunneling…
In Bi$_2$Te$_2$Se, the period of quantum oscillations arising from surface Dirac fermions can be increased 6-fold using ionic liquid gating. At large gate voltages, the Fermi energy reaches the $N$ = 1 Landau level in a 14-Tesla field. This…
A Bi2Se3 topological insulator field effect transistor is investigated by using ionic liquid as an electric double layer gating material, leading to a conductance modulation of 365% at room temperature. We discuss the role of charged…
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 periodic spatial modulation potential arising from the zig-zag distribution of ions at large gate voltage in an ionic liquid gated device may enable functionalities in a similar way as nanopatterning and moir\'e engineering. However,…
Topological insulators have been predicted to exhibit a variety of interesting phenomena including a quantized magnetoelectric response and novel spintronics effects due to spin textures on their surfaces. However, experimental observation…
The newly-discovered three-dimensional strong topological insulators (STIs) exhibit topologically-protected Dirac surface states. While the STI surface state has been studied spectroscopically by e.g. photoemission and scanned probes,…
Topological insulators are guaranteed to support metallic surface states on an insulating bulk, and one should thus expect that the electronic transport in these materials is dominated by the surfaces states. Alas, due to the high remaining…
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…
Electrically-conducting diamond is a promising candidate for next-generation electronic, thermal and electrochemical applications. One of the major obstacles towards its exploitation is the strong degradation that some of its key physical…