Broad response organic photodetectors (OPDs) with a photomultiplication (PM) effect are achieved with one absorber layer and one multiplication layer. The response range of the PM-OPDs is primarily determined by materials in the absorber layer, and the external quantum efficiency (EQE) of the PM-OPDs is mainly controlled by the multiplication layer. Here, double-layered PM-OPDs were designed with an ITO/ZnO/PM6:Y6/PC71BM:P3HT (100:5, w/w)/Au structure, where PM6:Y6 is employed as an absorber layer and PC71BM:P3HT is used as a multiplication layer. The optimal PM-OPDs exhibit a broad response covering 350–950 nm. Meanwhile, the optimal PM-OPDs exhibit the largest EQE value of ∼1200% and a maximum specific detectivity (D*) of ∼6.8 × 10–12 cm Hz1/2 W–1 under a 10 V bias. This double-layered approach may be a smart strategy for realizing PM-OPDs with an easily adjustable response range.

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Triplet acceptors have been developed to construct high‐performance organic solar cells (OSCs) as the long lifetime and diffusion range of triplet excitons may dissociate into free charges instead of net recombination when the energy levels of the lowest triplet state (T1) are close to those of charge‐transfer states (3CT). The current triplet acceptors were designed by introducing heavy atoms to enhance the intersystem crossing, limiting their applications. Herein, two twisted acceptors without heavy atoms, analogues of Y6, constructed with large π‐conjugated core and D‐A structure, were confirmed to be triplet materials, leading to high‐performance OSCs. The mechanism of triplet excitons were investigated to show that the twisted and D‐A structures result in large spin–orbit coupling (SOC) and small energy gap between the singlet and triplet states, and thus efficient intersystem crossing. Moreover, the energy level of T1 is close to 3CT, facilitating the split of triplet exciton to free charges.

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Udwadia-Kalaba approach which presents a new, general and explicit equation of motion for constrained mechanical systems with holonomic or nonholonomic constraints is applied to the trajectory tracking control of the mobile robot in this paper. Unlike any other nonlinear control methods, the inspiration for this methodology which does not make any linearization or approximations comes from a different, though closely allied, field, namely analytical dynamics. The control torques required to control the mobile robot so that it precisely satisfies the trajectory requirements which are represented by an arbitrary (sufficiently smooth) function of time are obtained explicitly and in closed form by solving Udwadia-Kalaba equation. Numerical simulations are performed to show the simplicity, efficacy and accuracy of this closed-form method.