Non-radiative recombination (NRR) of excited carriers poses a serious challenge to optoelectronic device efficiency. Understanding the mechanism is thus crucial to defect physics and technological applications. Here, by using first-principles calculations, we propose a new NRR mechanism, where excited carriers recombine via a Frenkel-pair (FP) defect formation. While in the ground state the FP ...

Supramolecular interactions between molecules of the same or different nature determine to a great extent degree their applicability in many fields science. To this regard, planar polycyclic aromatic hydrocarbons (PAHs) and nanometric congeners, nanographenes (NGs), as well positively curved ones, for instance corannulene, have been extensively explored. However, negatively saddle-shaped NGs re...

Defect prediction is the process of predicting the fault prone module using some pre-mined patterns or rules. Several statistical and mathematical strategies have been used in recent past to mine these rules. However, the interpretability of these rules is the matter of concern. In real development process an expert is required to demonstrate the working of mined patterns which prevents the use...

Solar cells made on boron-doped Czochralski (Cz) silicon show a degradation in performance when exposed to light until a stable efficiency is reached. This effect is due to the creation of metastable defects in the Cz silicon base which strongly reduce the bulk carrier lifetime. In a recent model, proposed by one of the authors, the metastable defect was tentatively identified with a boron-oxyg...

The cartoon figure on the cover image is Monkey King, who a character in classical Chinese novel “Journey to West”. He has 72 polymorphic transformations. As shown cartoon, he only needs blow breath and can create lot of little monkeys. p-Terphenylene-bridged NiII porphyrin dimer, which similar gave syn- anti-doubly heptagon-fused dimers, spiro-pentagon-bridged chlorin doubly octagon-fused dime...

Research on damage of gears and gear pairs using vibration signals remains very attractive, because vibration signals from a gear pair are complex in nature and not easy to interpret. Predicting gear pair defects by analyzing changes in vibration signal of gears pairs in operation is a very reliable method. Therefore, a suitable vibration signal processing technique is necessary to extract defe...