Photodetection Properties of MoS, WS and MoWS Heterostructure: A Comparative Study.

Layered transition metals dichalcogenides such as MoS and WS have shown a tunable bandgap, making them highly desirable for optoelectronic applications. Here, we report on one-step chemical vapor deposited MoS, WS and MoWS heterostructures incorporated into photoconductive devices to be examined and compared in view of their use as potential photodetectors. Vertically aligned MoS nanosheets and horizontally stacked WS layers, and their heterostructure form MoWS, exhibit direct and indirect bandgap, respectively.

10 kHz water-cooled Ti :Sapphire femtosecond laser.

We demonstrate operation of a simple and reliable water-cooled femtosecond laser running at 10 kHz suitable for industrial micromachining applications. A laser geometry involving only a regenerative amplifier and delivering 3.5 W average power 60-fs pulses is compared to a more conventional architecture using an additional multi-pass amplifier.