Plasma-based optical fiber tapering rig.

Optical fiber tapers have been widely proposed and demonstrated as reliable optical fiber structures for sensing, lasers, and supercontinuum generation applications. This paper proposes an innovative approach to fabricating optical fiber tapers using plasma as the heat source. From our literature review, and to the best of our knowledge, this is the first time that plasma has been used as the heat source for producing optical fiber tapers.

Sub-wavelength scale characterization of on-chip coupling mirrors.

Miniature free-space optical beams, originating from on-chip microstructures, are usually measured and quoted without reference to a particular polarization state. We develop an automated platform to characterize tightly focused free-space optical beams in three dimensions. We present a detailed description of each subsystem including the calibration and test procedure.

Disentangling Hot Carrier Decay and the Nature of Low- to High- Transfer Processes in Quasi-Two-Dimensional Layered Perovskites.

Quasi-two-dimensional (2D) metal halide perovskites (MHPs) are promising photovoltaic (PV) materials because of their impressive optical and optoelectronic properties and improved stability compared to their 3D counterparts. The presence of domains with varying numbers of inorganic layers between the organic spacers (-phases), each with different bandgaps, makes the photoinduced carrier dynamics in films of these materials complex and intriguing. Existing interpretations of the ultrafast femto- or picosecond spectroscopy data have been inconsistent, most of them focusing either on exciton/charge transfer from low- to high- phases or on hot carrier cooling, but not combined.

Quantitative comparison of excitation modes of tuning forks for shear force in probe microscopy.

This article provides a careful comparison between the electric and mechanical excitation of a tuning fork for shear force feedback in scanning probe microscopy, an analysis not found in present literature. A setup is designed and demonstrated for robust signal and noise measurements at comparable levels of physical movement of the probe. Two different signal amplification methods, combined with two excitation ways provide three possible configurations.

Unraveling the Mechanisms of Beneficial Cu-Doping of NiO-Based Photocathodes.

Dye-sensitized photoelectrochemical (DSPEC) water splitting is an attractive approach to convert and store solar energy into chemical bonds. However, the solar conversion efficiency of a DSPEC cell is typically low due to a poor performance of the photocathode. Here, we demonstrate that Cu-doping improves the performance of a functionalized NiO-based photocathode significantly.