An efficient light trapping scheme is a key to enhancing the power conversion efficiency (PCE) of thin-film photovoltaic (PV) cells by compensating for the insufficient light absorption. To handle optical components from nano-scale to micro-scale seamlessly, a multi-scale optical simulation is carefully designed in this study and is used to qualitatively analyze the light trapping performances ...

In high resolution absorption spectrometers with conventional light sources, the signal-to-noise ratio (SNR) is usually limited by the thermal noise level of the detector-preamplifier combination, which is independent of the light source power. However, the noise in many laser absorption spectrometers is dominated by the excess or shot noise which is dependent on the transmitted laser power, an...

the absorption properties of charge transfer organic semiconductor ttf-tcnq (tetrathiafulvalene-tetracyanoquhodimete ) filmsdeposited on kbr singlecrystal, quartz and glass substrates in far infrared have been investigated. an absorption edge at ?10 ??m was observed. photoconductivity, photoconduction efficiency and gain and photocarrier's lifetime have been measured. the results show an e...

We use theoretical models to compare the receiver signal to noise ratio (SNR) vs. average rate of detected signal photons for an integrated path differential absorption (IPDA) lidar using coherent detection with continuous wave (CW) lasers and direct detection with sine-wave and pulse modulations. The results show the coherent IPDA lidar has high receiver gain and narrow bandwidth to overcome t...

Seventeen two-photon transitions for neon have been observed in the 580- 635 nm spectral region for use in the spectroscopic study of its higher excited levels, which are not accessible by one-photon absorption. To compare the two and one-photon absorption signals originating from the same lower level, an effort was made to record single-photon optogalvanic spectrum in the available wavele...

High-molecular gel containing capsulate thermo-chromic liquid crystal is made to visualize three-dimensional distribution of electromagnetic power absorption. A preliminary experiment is performed at frequency of 1.5GHz. As a result of the experiment, the three-dimensional distribution of electromagnetic power absorption is clearly visualized. The result shows that the gel can be used as a phan...

MoS2, as a typical transition metal dichalcogenide, has attracted great interest because of its distinctive electronic, optical, and catalytic properties. However, its advantages of strong light absorption and fast intralayer mobility cannot be well developed in the usual reported monolayer/few-layer structures, which make the performances of MoS2-based devices undesirable. Here, large-area, hi...

Thin film photovoltaic (PV) technologies are highly attractive for low-cost solar energy conversion and possess a wide range of potential applications from building-integrated PV generation to portable power sources. Inverted nanocones (i-cones) have been demonstrated as a promising structure for practical thin film PV devices/modules, owning to their antireflection effect, self-cleaning functi...

We consider absorption refrigerators consisting of simultaneously operating Carnot-type heat engine and refrigerator. Their maximum efficiency at given power (MEGP) is by the product MEGPs for internal The only subtlety derivation lies in fact that cooling refrigerator not limited just refrigerator, but, due to first law, also engine. As a specific example, we simultaneous composed low-dissipat...