2D transition metal dichalcogenides are attracting increased attention because of their excellent electronic and optical properties. Inspired by the natural weathering exfoliation of seaside rocks, a “chemical weathering” concept for fabricating atom‐thick 2D materials from their bulk counterparts is proposed. It is experimentally demonstrated that chemical weathering‐assisted exfoliation mechanism is a simple and efficient method of preparing atom‐thick MoS2 and WS2 monolayers. These monolayers are difficult to prepare using other approaches. Interestingly, the as‐prepared MoS2 and WS2 monolayers exhibit excellent saturable absorption and mode‐locking properties in all‐solid‐state lasers because of intermediate states resulting from S‐vacancy defects. The obtained passively Q‐switched laser operation with 60 ns pulse width and ultrafast mode locking with 8.6 ps pulse width are promising for all‐solid‐state laser application.

Using an optical parametric oscillation laser as the excitation source, the dependence of the saturable absorption of multiple-layer graphene upon photon energy is investigated and, in all cases, the saturation intensity is lower for lower excitation photon energy. This result experimentally proves the hourglass shape of the energy band of graphene, which is a well-known theoretical deduction from first principles. The modulation depth increases from 1.5% to 5.1% when the layer number increases from a monolayer to 5–7 layers and, at the same time, the saturation intensity decreases with increasing number of layers. The results demonstrate that, as a saturable absorber of a pulsed laser, graphene can more easily achieve optical modulation in the low energy region, i.e., the infrared waveband.

We report a novel strategy for optical temperature sensing using the temperature-induced red shift of the charge transfer band (CTB) edge of the VO groups in GdVO:5% Sm. Excitation spectra were recorded at a series of temperatures ranging from 300 to 480 K. It is demonstrated that an excitation intensity of around 360 nm corresponding to the tail of the CTB and an excitation intensity of 407.6 nm corresponding to the H → F transition of Sm exhibit opposite temperature dependence. Based on this, the relative sensitivity was obtained to be 3313/T in our investigated temperature range, which is remarkable progress compared with the optical temperature sensors reported previously. We believe that this work broadens the pathway for the design of highly sensitive temperature sensing materials.

On-chip microvalves regulate electrical and fluidic access to an array of nanopores integrated within microfluidic networks. This configuration allows for on-chip sequestration of biomolecular samples in various flow channels and analysis by independent nanopores.

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We demonstrate the optical orbital angular momentum conservation during the transfer process from subwavelength plasmonic vortex lens (PVLs) to light and the generating process of surface plasmon polaritons (SPPs). Illuminating plasmonic vortex lenses with beams carrying optical orbital angular momentum, the SP vortices with orbital angular momentum were generated and inherit the optical angular momentum of light beams and PVLs. The angular momentum of twisting SP electromagnetic field is tunable by the twisted metal/dielectric interfaces of PVLs and angular momentum of illuminating singular light. This work may open the door for several possible applications of SP vortices in subwavelength region.

With the increasing number of female senior executives, the relationship between female senior executives and corporate innovation behaviors has attracted widespread attention, but few works have studied the influences of female CEOs on innovation behaviors and their mechanisms. This paper studies the relationship between CEO's gender and the selection of corporate innovation behaviors, as well as the regulating effect of gender culture on the relationship between them. It was discovered in the studies that (1) if compared with male CEOs, female CEOs have significantly promoted both incremental innovation behaviors and radical innovation behaviors; (2) gender culture has positively regulated the relationship between CEO's gender and corporate incremental innovation behaviors, yet the regulating effect of gender culture on the relationship between CEO's gender and corporate radical innovation behaviors is not significant. Thus, the government needs to further foster a gender culture with gender equality, and actively promote the positive effect of female CEOs in corporate innovations.