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Here, we demonstrate an efficient nanocomposite system for the enhancement of optical properties via a self-assembled 2D nanoarchitecture combined with insulating and conducting polymers. The excitonic properties of the ternary composites consisting of MoS2 nanosheets, poly methyl methacrylate (PMMA), and polyaniline (PANI) (MPP) were tuned by optimizing the concentration of PANI. Their absorption spectra revealed a strong excitonic coupling between the components. The mechanisms of exciton dissociation and generation of interlayer excitons were investigated by steady-state and transient photoluminescence spectroscopy. The exciton decay time is reduced by almost 95% in the ternary composite at an optimized concentration of PANI than in pure MoS2. This indicates a fast excitonic interaction between MoS2 and PANI in the presence of the insulating polymer PMMA. Furthermore, nonlinear optical studies using the z-scan technique further confirmed the exciton–exciton coupling in the ternary composites. Therefore, these ternary composites having multiple excitons and strong saturable absorption (SA) behavior provide a perspective for next-generation saturable absorber devices and other optoelectronic applications.

The investigation of excitons in atomically thin MoS 2 and its hybrid materials with other semiconductors has gained immense attention, considering its emerging application in light-harvesting systems. However, they suffer from agglomeration while employing on a large scale. To resolve this problem, polymer composites with heterostructures are needed. Designing ternary nanocomposite-based light-harvesting devices is the next step forward for achieving high-performance electron transfer properties. Here, we have synthesized ZnO@MoS 2 core−shell heterostructures and modified the surface of the heterostructure with polyaniline (PANI) molecules. In this ternary composite system, PANI is a conducting polymer that constantly transports electrons to the neighboring conduction band of MoS 2 . A transient photoluminescence study suggests that the rate of exciton decay in the ternary composite system is 6.41 ns at the highest concentration of PANI, which is faster than in bare MoS 2 . The tuning of exciton diffusion length was also achieved by changing the concentration of PANI, which is a useful parameter for any photodetectors. As a proof of concept, the as-fabricated core−shell heterostructure film integrated with PANI is applied as a photosensitive device and we have observed a nearly 3-fold enhancement of photocurrent under irradiation of visible light, indicating that this type of semiconductor/ polymer composite is a very prospective system for future solar light harvesting.

In this study, a layered nanoporous structure of Cr-doped zinc oxide (ZnO) was synthesized by a simple hydrothermal and post-annealing technique. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet (UV)−visible spectroscopy techniques. The XRD peak shift provides additional evidence of the incorporation of the dopant. Field emission scanning electron microscopy was used to confirm the porous morphology. From high-resolution transmission electron microscopy pictures, the pore size and crystallographic layouts were calculated. UV−vis spectra demonstrated that the absorbance improved, and a reduction in band gap was observed with an increment in dopant concentration. The vibrational modes of the produced ZnO sample were analyzed by Raman spectroscopy, which confirmed the absence of other contaminants. Upon addition of the dopant, the phonon peaks showed asymmetric broadening caused by the interaction of discrete states with continuum states. Due to the strong contact, the asymmetry got worse as the dopant concentration increased. Finally, current−voltage (I−V) measurements indicated a great enhancement after Cr doping in UV photoresponse. The UV light detection phenomenon can be ascribed to the trapping and detrapping of electrons by Cr-related defects.

In this Letter, a reconfigurable processing element (PE) for pipelined SDF FFT architecture is presented, which can be configured to compute 2, 3 and 5-point DFTs. Foremost, the proposed PE architecture for the 5-point DFT computation is designed by factorising the 5-point DFT computation operation into 2 × 2 cyclic convolution units and then the 2-and 3-point DFTs structures are mapped on to it using multiplexers. Thus, all three configurations are possible. In the case of prior 5-point PE designs, the PE can start its operation only after the arrival of all the five-input data, whereas the proposed PE completes a part of computation after the arrival of the first three inputs and reuse the same hardware to process the next two inputs. As a result, the proposed PE requires less hardware, at the same time, preserving the throughput of prior PE. The proposed PE required 25% less multiplier and one adder less compared to the Winograd algorithm based 5-input PE.

Fabrication of optical components such as passive optics (mirrors, prisms, lenses) or active optics (polarizer's, laser gain media, adaptive optics) starts from a bulk material and reaches to the required size and shape. To achieve the required specification of the component, a series of process has to be followed from grinding to polishing stage. Initially, in grinding stage, material removal is faster, with more surface damage and less geometric control. During polishing stage, material removal is slower, with no surface damage but with greater geometric control. Hence, to achieve good surface quality, the component or work piece has to be controlled from grinding stage. We present an advanced surface and fractal analysis study on fused silica samples processed with different grit sizes such as 3, 5, 12, and 25 μm aluminium oxide (Al 2 O 3 ) abrasives. The maximum sub surface damage (SSD) with respect to size of the abrasive grain ranged between 30 μm to 5 μm in empirical module. In theoretical module it varied from 45 μm to 5.4 μm for fused silica glass, mediated with loose abrasive aluminium oxide powder of 25 μm and 3 μm respectively. An experimental investigation is reported on the increasing effect of Al 2 O 3 grit sizes on the surface topography such as average roughness (Ra), which varied from 57 nm to 847 nm for 3 μm and 25 μm Al 2 O 3 abrasives respectively. Three-dimensional image analysis was captured through Phase Shift Interferometry (PSI) and Coherence Correlation Interferometer (CCI) technique. Field Emission Scanning Electron Microscope (FESEM) technique was utilized to characterize the Al 2 O 3 powders and the processed fused silica samples. Later, the images have been analysed using two-dimensional multifractal detrended fluctuation analysis (2D-MFDFA) to understand and confirm the multiple fractal nature on fused silica samples caused by varying grit size of Al 2 O 3 abrasives.