Design of low‐order controllers satisfying sensitivity constraints for unstructured uncertain plants

This paper presents a simple analytically based algorithm for the design of reduced‐order controllers satisfying frequency‐dependent sensitivity specifications for SISO plants having unstructured uncertainty. The uncertainties can be additive as well as multiplicative, and can take the form of circles, polygons or sectors located around a nominal plant. Moreover, the circle radius and polygon and sector sizes may depend on the frequency. The proposed method is applicable to both continuous and discrete designs. Copyright © 2004 John Wiley & Sons, Ltd.     

Color tuning of indium phosphide quantum dots for cadmium‐free quantum dot light‐emitting devices with high efficiency and color saturation

Semiconductor quantum dots (QDs) promise facile color tuning and high color saturation in quantum‐dot light‐emitting devices (QD‐LEDs) by controlling nanoparticle size and size distribution. Here, we demonstrate how this promise can be practically realized for the cadmium‐free InP/ZnSe/ZnS multishell quantum dots. We developed a set of synthesis conditions and core/shell compositions that result in QDs with green, yellow, and red emission color. The QD‐LEDs employing these QDs show efficient electroluminescence (EL) with luminance up to 1800 cd/m² and efficiency up to 5.1 cd/ A . The color coordinates calculated from the EL spectra clearly demonstrate the outstanding color saturation as an outcome of the narrow particle size distribution. These results prove that the performance gap between cadmium‐free and cadmium‐based QDs in QD‐LEDs is shrinking rapidly.     

Finite horizon H∞ control for a class of sampled‐data linear quantum systems

In this paper, a finite horizon H^∞ control problem is solved for a class of linear quantum systems using a dynamic game approach for the case of sampled‐data measurements. The methodology adopted involves an equivalence between the quantum problem and two auxiliary classical problems. Copyright © 2016 John Wiley & Sons, Ltd.