A Pd-catalyzed decarboxylative coupling of thiazoles and benzoxazole with various substituted benzoic acids is developed. The reaction is compatible with both electron-rich and electron-poor benzoic acids. It can also be extended to the synthesis of polyfluoro-substituted biaryls using polyfluorobenzenes as the starting materials.

The effect of a coherence resonance is observed experimentally in a GaAs/Al_{0.45}Ga_{0.55}As superlattice under dc bias at room temperature, which is driven by noise. For an applied voltage, for which no current self-oscillations are observed, regular current self-oscillations with a frequency of about 82 MHz are induced by exceeding a certain noise amplitude. In addition, a novel kind of a stochastic resonance is identified, which is triggered by the coherence resonance. This stochastic resonance appears when the device is driven by an external ac signal with a frequency, which is relatively close to that of the regular current self-oscillations at the coherence resonance. The intrinsic oscillation mode in the coherence resonance is found to be phase locked by an extremely weak ac signal. It is demonstrated that an excitable superlattice device can be used for the fast detection of weak signals submerged in noise. These results are very well reproduced by results using numerical simulations based on a sequential resonant tunneling model of nonlinear electron transport in semiconductor superlattices.

We present an analysis of crosstalk in aligned and misaligned free-space optical interconnect (FSOI) systems. On the basis of a generalized diffraction integral formula, an analytical expression of irradiation distribution for FSOI systems and a convenient approach to calculate crosstalk noise signal ratios (CNSR) are proposed. Simulations are performed to analyze the factors affecting the CNSR. The analyses indicate that small beam quality factor and wide channel pitch will significantly improve performance of the FSOIs. Furthermore, the displacement of the transmitter microlens array will affect the interconnection distance much more significantly than that of the receiver microlens array.

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By carefully choosing the right substrate ratio, catalyst combination, and base, symmetrical and unsymmetrical biaryls can be readily synthesized through the Pd‐catalyzed decarboxylative homo‐ and heterocoupling of substituted benzoic acids. The reaction gave the desired products in 40–90 % yield and is compatible with 2‐nitro‐, 2‐methoxy‐, 2‐fluoro‐, and 2‐chloro‐substituted benzoic acids.