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While the promise of clean and defect-free $\textrm{MoS}_{2}$ nanotubes as quantum electronic devices is obvious, ranging from strong spin-orbit interaction to intrinsic superconductivity, device fabrication still poses considerable challenges. Deterministic transfer of transition metal dichalcogenide nanomaterials and transparent contacts to the nanomaterials are nowadays highly active topics of research, both with fundamental research and applications in mind. Contamination from transport agents as well as surface adsorbates and surface charges play a critical role for device performance. Many techniques have been proposed to address these topics for transition metal dichalcogenides in general. Here, we analyse their usage for the transfer based fabrication of $\textrm{MoS}_{2}$ nanotube devices. Further, we compare different contact materials in order to avoid the formation of a Schottky barrier., Comment: 10 pages, 8 figures

A current was injected into a single MoS2 nanotube using an atomic-force-microscopy probe. The trapped electrons and holes caused a partial collapse of the nanotube and its helical twisting. The topography changes can be explained by the reverse piezoelectric effect, the theory of which was proposed for chiral nanostructures. Work-function modifications were observed, which were dependent on the polarity of the injected carriers., Comment: 8 pages, 6 figures

A single nanotube synthesized from a transition metal dichalcogenide (TMDC) exhibits strong exciton resonances and, in addition, can support optical whispering gallery modes. This combination is promising for observing exciton-polaritons without an external cavity. However, traditional energy-momentum-resolved detection methods are unsuitable for this tiny object. Instead, we propose to use split optical modes in a twisted nanotube with the flattened cross-section, where a gradually decreasing gap between the opposite walls leads to a change in mode energy, similar to the effect of the barrier width on the eigenenergies in the double-well potential. Using micro-reflectance spectroscopy, we investigated the rich pattern of polariton branches in single MoS$_2$ tubes with both variable and constant gaps. Observed Rabi splitting in the 40 - 60 meV range is comparable to that for a MoS$_2$ monolayer in a microcavity. Our results, based on the polariton dispersion measurements and polariton dynamics analysis, present a single TMDC nanotube as a perfect polaritonic structure for nanophotonics.

Molybdenum disulfide nanoribbons and nanotubes are quasi-1D semiconductors with strong spin-orbit interaction, a nanomaterial highly promising for quantum electronic applications. Here, it is demonstrated that a bismuth semimetal layer between the contact metal and this nanomaterial strongly improves the properties of the contacts. Two-point resistances on the order of 100k$\Omega$ are observed at room temperature. At cryogenic temperature, Coulomb blockade is visible. The resulting stability diagrams indicate a marked absence of trap states at the contacts and the corresponding disorder, compared to previous devices that use low-work-function metals as contacts. Single-level quantum transport is observed at temperatures below 100mK., Comment: published version (open access); 7 pages, 5 figures

Nanotubes (NTs) of transition metal dichalcogenides (TMDs), such as MoS2 and WS2, were first synthesized more than a quarter of a century ago; nevertheless, many of their properties have so far remained basically unknown. This review presents the state of the art in the knowledge of the optical properties of TMD NTs. We first evaluate general properties of multilayered TMD crystals, and analyze available data on electronic band structure and optical properties of related NTs. Then, the technology for the formation and the structural characteristics of TMD NTs are represented, focusing on the structures synthesized by chemical transport reaction. The core of this work is the presentation of the ability of TMD NTs to emit bright photoluminescence (PL), which has been discovered recently. By means of micro-PL spectroscopy of individual tubes we show that excitonic transitions relevant to both direct and indirect band gaps contribute to the emission spectra of the NTs despite the presence of dozens of monolayers in their walls. We highlight the performance of the tubes as efficient optical resonators, whose confined optical modes strongly affect the emission bands. Finally, a brief conclusion is presented, along with an outlook of the future studies of this novel member of the family of radiative NTs, which have unique potential for different nanophotonics applications., Comment: 38 pages, 11 fugures, 106 references

We study the optical properties of MoS$_2$ nanotubes (NTs) with walls comprising dozens of monolayers. We reveal strong peaks in micro-photoluminescence ($\mu$-PL) spectra when detecting the light polarized along the NT axis. We develop a model describing the optical properties of the nanotubes acting as optical resonators which support the quantization of whispering gallery modes inside the NT wall. The experimental observation of the resonances in $\mu$-PL allows one to use them as a contactless method of the estimation of the wall width. Our findings open a way to use such NTs as polarization-sensitive components of nanophotonic devices., Comment: 7 pages, 4 figures

Charge transport measurements on flexible Mo$_{6}$S$_{3}$I$_{6}$ (MoSI) nanowires with different diameters in highly imperfect 2-terminal circuits reveal systematic power law behaviour of the conductivity $\sigma(T,V)$ as a function of temperature and voltage. On the basis of measurements on a number of circuits we conclude that the behaviour in \emph{thin} wires can be most convincingly described by tunneling through Tomonaga-Luttinger liquid (TLL) segments of MoSI wire, which is in some cases modified by environmental Coulomb blockade (ECB). The latter are proposed to arise from deformations or imperfections of the MoSI wires, which - in combination with their recognitive terminal sulfur-based connectivity properties - might be useful for creating sub-nanometer scale interconnects as well as non-linear elements for molecular electronics., Comment: 7 pages, 8 figures