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Abstract Strain modulation is a crucial way in engineering nanoscale materials. It is even more important for single photon emitters in layered materials, where strain can trap a delocalized exciton, leading to quantum emission. Herein, we apply strain by using the piezoelectric relaxor ferroelectric substrate. In addition to the strain-tuning of energy and polarization, we report on new observations, including the enhanced polarizability and tunable diamagnetic shift, from the charged localized excitons. As indicated from the polarization-resolved measurements, we attribute the formation of charged localized excitons to selenium vacancy defects. The shallow defect trap, supported by the value of g-factor, further allows for strain-modulation of the electron-hole overlap, hence resulting in the tunable diamagnetic shift. Our results provide a new perspective in integrating layered materials with functional substrates. The contrasting features observed from the charged localized excitons also signify the prospect of charged localized emitters for quantum science and technology. 

AbstractClick to copy section link One-dimensional (1D) ternary transition metal chalcogenides (M2X3Y8) have emerged as a promising class of materials for advanced electronic and optoelectronic applications. This Mini-Review comprehensively explores recent advancements in their synthesis, characterization, and integration into functional devices. The studied nanowires display exceptional performance as semiconductor 1D nanostructures in photodetection, field-effect transistors, and gas sensing. Their unique 1D structure, tunable electronic properties, and high stability make them attractive candidates for future research and development in the field of materials science. 

Immediately after the demonstration of the high-quality electronic properties in various two dimensional (2D) van der Waals (vdW) crystals fabricated with mechanical exfoliation, many methods have been reported to explore and control large scale fabrications. Comparing with recent advancements in fabricating 2D atomic layered crystals, large scale production of one dimensional (1D) nanowires with thickness approaching molecular or atomic level still remains stagnant. Here, we demonstrate the high yield production of a 1D vdW material, semiconducting Ta2Pd3Se8 nanowires, by means of liquid-phase exfoliation. The thinnest nanowire we have readily achieved is around 1 nm, corresponding to a bundle of one or two molecular ribbons. Transmission electron microscopy (TEM) and transport measurements reveal the as-fabricated Ta2Pd3Se8 nanowires exhibit unexpected high crystallinity and chemical stability. Our low-frequency Raman spectroscopy reveals clear evidence of the existing of weak inter-ribbon bindings. The fabricated nanowire transistors exhibit high switching performance and promising applications for photodetectors. 

Abstract Here, a new family of 2D transition metal carbo‐chalcogenides (TMCCs) is reported, which can be considered a combination of two well‐known families, TM carbides (MXenes) and TM dichalcogenides (TMDCs), at the atomic level. Single sheets are successfully obtained from multilayered Nb₂S₂C and Ta₂S₂C using electrochemical lithiation followed by sonication in water. The parent multilayered TMCCs are synthesized using a simple, scalable solid‐state synthesis followed by a topochemical reaction. Superconductivity transition is observed at 7.55 K for Nb₂S₂C. The delaminated Nb₂S₂C outperforms both multilayered Nb₂S₂C and delaminated NbS₂as an electrode material for Li‐ion batteries. Ab initio calculations predict the elastic constant of TMCC to be over 50% higher than that of TMDC.