Quantum computing measurement and intelligence

One of the grand challenges in the nanoscopic computing era is guarantees of robustness. Robust computing system design is confronted with quantum physical, probabilistic, and even biological phenomena, and guaranteeing high‐reliability is much more difficult than ever before. Scaling devices down to the level of single electron operation will bring forth new challenges due to probabilistic effects and uncertainty in guaranteeing “zero‐one” based computing. Minuscule devices imply billions of devices on a single chip, which may help mitigate the challenge of uncertainty by replication and redundancy. However, such device densities will create a design and validation nightmare with the sheer scale. The questions that confront computer engineers regarding the current status of nanocomputing material and the reliability of systems built from such minuscule devices are difficult to articulate and answer. This article illustrates and discusses two types of quantum algorithms as follows: (1) a simple quantum algorithm and (2) a quantum search algorithm. This article also presents a review of recent advances in quantum computing and intelligence and presents major achievements and obstacles for researchers in the near future. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010     

Intracellular Assembly of Interacting Enzymes Yields Highly-Active Nanoparticles for Flow Biocatalysis

All-enzyme hydrogel (AEH) particles with a hydrodynamic diameter of up to 120 nm were produced intracellularly with an Escherichia coli-based in vivo system. The inCell-AEH nanoparticles were generated from polycistronic vectors enabling simultaneous expression of two interacting enzymes, the Lactobacillus brevis alcohol dehydrogenase (ADH) and the Bacillus subtilis glucose-1-dehydrogenase (GDH), fused with a SpyCatcher or SpyTag, respectively. Formation of inCell-AEH was analyzed by dynamic light scattering and atomic force microscopy. Using the stereoselective two-step reduction of a prochiral diketone substrate, we show that the inCell-AEH approach can be advantageously used in whole-cell flow biocatalysis, by which flow reactors could be operated for >4 days under constant substrate perfusion. More importantly, the inCell-AEH concept enables the recovery of efficient catalyst materials for stable flow bioreactors in a simple and economical one-step procedure from crude bacterial lysates. We believe that our method will contribute to further optimization of sustainable biocatalytic processes.     

N‐Trifluoromethyl Hydrazines,Indoles and Their Derivatives

Reported herein is the first efficient strategy to synthesize a broad range of unsymmetrical N‐CF₃ hydrazines, which served as platform to unlock numerous currently inaccessible derivatives, such as tri‐ and tetra‐substituted N‐CF₃ hydrazines, hydrazones, sulfonyl hydrazines, and valuable N‐CF₃ indoles. These compounds proved to be remarkably robust, being compatible with acids, bases, and a wide range of synthetic manipulations. The feasibility of RN(CF₃)‐NH₂ to function as a directing group in C?H functionalization is also showcased.     

Effect of pressure and space between electrodes on the deposition of SiN_xH_y films in a capacitively coupled plasma reactor

The fluid model, also called the macroscopic model, is commonly used to simulate low temperature and low pressure radiofrequency plasma discharges. By varying the parameters of the model, numerical simulation allows us to study several cases, providing us the physico-chemical information that is often difficult to obtain experimentally. In this work, using the fluid model, we employ numerical simulation to show the effect of pressure and space between the reactor electrodes on the fundamental properties of silicon plasma diluted with ammonia and hydrogen. The results show the evolution of the fundamental characteristics of the plasma discharge as a function of the variation of the pressure and the distance between the electrodes. By examining the pressure-distance product in a range between 0.3 Torr 2.7 cm and 0.7 Torr 4 cm, we have determined the optimal pressure-distance product that allows better deposition of hydrogenated silicon nitride(Si N_x H_y)films which is 0.7 Torr 2.7 cm.     

Optical channel drop filters based on photonic crystal ring resonators

A new optical channel drop filters (CDFs) configuration based on photonic crystals ring resonators (PCRRs) is provided. The transmission characteristics for single-ring and multiple-ring configurations have been investigated by using the two-dimensional (2D) finite-difference time-domain (FDTD) technique in triangular lattice photonic crystal (PC) silicon rods. Both forward and backward dropping were achieved in dual-ring PCRR structures. In this filter, 100% drop efficiency and acceptable quality factor can be obtained at 1550 nm. The present device can be used in the future photonic integrated circuits.     

Electronic states and the Stark shift in narrow band InSb quantum spherical layer

Electron states and the Stark shift in narrow band quantum spherical InSb layers are considered in frameworks of Kane model with respect to non-parabolicity of the dispersion law. An exact analytical solution of the corresponding Klein–Gordon equation for the model of impenetrable walls is obtained, and in addition to that a transcendent equation for determination of electron energetic spectrum is derived as well. The influence of the electric field is considered in frames of the perturbation theory, it is also shown that the value of the Stark shift is proportional to the second power degree of the field. Dependences of the electron energy versus the internal field values, external radius, and electric field are presented. The obtained results are compared with results obtained for the case with standard dispersion.     

The regioselectivity of the ring opening of 1-activated or nonactivated 2-alkoxycarbonyl or 2-cyanoaziridines by carbanions of the dicarbonyl compounds

Ring opening of title compounds with alkyl malonates, acetylacetone, methyl acetylacetate, and malononitrile was studied. The regioselectivity of the opening depends on several factors. A phenyl group on C? 3 favours C? 3? N bond cleavage, whereas C? 2? N bond cleavage is predominant with C? 3-substituted or C? 2? H aziridines. Cyanoaziridines are predominantly cleaved at C? 3? N. The aziridine configuration at C? 2 and C? 3 is maintained during the cyclisation in pyrrolidones.     

Investigating Route to Chaos in Nonlinear Plasmonic Dimer

The route to chaos of a plasmonic dimer formed of two identical nanoparticles with Kerr-type nonlinear response and illuminated by an external electric field is reported. It is shown that this system has a complex dynamical behavior with chaotic nature. This complexity is analyzed using Lyapunov exponents, the Kaplan–Yorke dimension, and correlation dimensions. The existence of familiar period-doubling sequences route to chaos is pointed out, and domains corresponding to the onset of period doubling and chaos in the plane of parameters are evidenced.     

1.55 μm strained layer multiple quantum well DFB-lasers with low chirp and low distortions for optical analog CATV distribution systems

Strained layer multiple quantum-well 1.55 μm DFB-lasers with extremely low chirp and low intermodulation distortions were made. System experiments with transmission of more than 35 analog modulated TV and Radio carriers over 32 km of standard fiber were performed.