Modulation of the Superconducting Phase Transition in Multilayer 2H-NbSe Induced by Uniform Biaxial Compressive Strain.

Strain is a powerful tool for tuning the properties of two-dimensional materials. Here, we investigated the effects of large, uniform biaxial compressive strain on the superconducting phase transition of multilayered 2H-NbSe flakes. We observed a consistent decrease in the critical temperature of NbSe flakes induced by the large thermal compression of a polymeric substrate (>1.

Tunable, multifunctional opto-electrical response in multilayer FePS/single-layer MoS van der Waals p-n heterojunctions.

The combination of specific van der Waals semiconductors in vertical stacks leads to atomically sharp heterointerfaces with unique properties, offering versatility and additional functionality for thin, flexible, optoelectronic devices. In this work, we demonstrate heterostructures built from single-layer MoS (n-type) and multilayer FePS (p-type) as multifunctional p-n junctions where robust photoluminescent light emission and broadband electrical photo-response coexist. This is made possible by the inherent properties of the materials involved and the precise energy band alignment at their interface, which preserves the photoluminescent emission provided by the single-layer MoS and confers exceptional tunability to the system.

Large Biaxial Compressive Strain Tuning of Neutral and Charged Excitons in Single-Layer Transition Metal Dichalcogenides.

The absorption and emission of light in single-layer transition metal dichalcogenides are governed by the formation of excitonic quasiparticles. Strain provides a powerful technique to tune the optoelectronic properties of two-dimensional materials and thus to adjust their exciton energies. The effects of large compressive strain in the optical spectrum of two-dimensional (2D) semiconductors remain rather unexplored compared to those of tensile strain, mainly due to experimental constraints.

Photoluminescence Enhancement by Band Alignment Engineering in MoS/FePS van der Waals Heterostructures.

Single-layer semiconducting transition metal dichalcogenides (2H-TMDs) display robust excitonic photoluminescence emission, which can be improved by controlled changes to the environment and the chemical potential of the material. However, a drastic emission quench has been generally observed when TMDs are stacked in van der Waals heterostructures, which often favor the nonradiative recombination of photocarriers. Herein, we achieve an enhancement of the photoluminescence of single-layer MoS on top of van der Waals FePS.