Width-Dependent, Layer Controlled Growth of TMD Quantum Nanoribbons

Introducing additional degrees of freedom provided by the number of the layers, the width, and the strain of two-dimensional transition metal dichalcogenide (TMD) materials opens a new perspective for tuning their properties aiming at applications in quantum electronics and photonics. However, there is no facile, controllable growth method of TMD nanoribbons, especially for the appealing width range below 30 nm. Here we report a new method for growing single and double atomic layer of MeX₂ nanoribbons (Me=Mo, W; X=S, Se) with width down to sub-10 nm. The nanoribbon growth occurs via precipitation from pre-deposited seed nanoparticles with properly selected constituents in a chalcogen vapor atmosphere. We found linear dependence of growth rate on supersaturation, known as a criterion for continues growth mechanism, which decreases with decreasing of NR width driven by the Gibbs-Thomson effect. The grown bilayers nanoribbons demonstrate remarkable elastic robustness with strain up to ~14%. By applying external strains, TMD single layer nanoribbons generate high performance quantum emission of up to ~90% single photon purity, which is indicative of strain-induced localized electronic states. Moreover, width-dependent Coulomb blockade oscillations are observed in the transfer characteristics of MoS₂ nanoribbons with width &lt;20 nm at temperatures up to 80 K due to the single electron transfer. Our new synthesis method provides a general route for width-controllable growth of families of atomic layer quantum nanoribbons, paving a pathway to the synthesis of novel quantum materials.<br/> <br/><b>References</b><br/>X. Li., et al. <i>ACS Nano</i><b> 14, </b>6570 (2020).<br/>X. Li., et al. <i>Sci. Adv.</i> 7 (50), eabk1892 (2021).