Optical engineering of infrared PbS CQD photovoltaic cells for wireless optical power transfer systems.

Infrared photovoltaic cells (IRPCs) have attracted considerable attention for potential applications in wireless optical power transfer (WOPT) systems. As an efficient fiber-integrated WOPT system typically uses a 1550 nm laser beam, it is essential to tune the peak conversion efficiency of IRPCs to this wavelength. However, IRPCs based on lead sulfide (PbS) colloidal quantum dots (CQDs) with an excitonic peak of 1550 nm exhibit low short circuit current (J) due to insufficient absorption under monochromatic light illumination.

Raman tensor of layered MoS.

Raman tensors, one of the basic physical properties of ${{\rm MoS}_2}$MoS, are rarely reported. Here, angle-resolved polarized Raman scatterings on basal and cross planes of layered ${{\rm MoS}_2}$MoS were carried out using the geometry configuration of parallel polarization, and the Raman tensors of three optical vibration modes were systematically studied. As a polar vibration mode, the differential polarizability of the ${{\rm A}_{1{\rm g}}}$A mode corresponding to the Raman tensor along the $c$c direction is larger than that along the $a$a direction.