Aviation Law Comes Home to the Main Street Lawyer

Well controlled in length and highly aligned ZnO nanorods were grown on the gold-coated glass substrate by hydrothermal growth method. ZnO nanorods were functionalised with selective thallium (I) ion ionophore dibenzyldiaza-18-crown-6 (DBzDA18C6). The thallium ion sensor showed wide linear potentiometric response to thallium (I) ion concentrations ( M to  M) with high sensitivity of 36.87 ± 1.49 mV/decade. Moreover, thallium (I) ion demonstrated fast response time of less than 5 s, high selectivity, reproducibility, storage stability, and negligible response to common interferents. The proposed thallium (I) ion-sensor electrode was also used as an indicator electrode in the potentiometric titration, and it has shown good stoichiometric response for the determination of thallium (I) ion

Weak antilocalization in quantum wells in tilted magnetic fields

Weak antilocalization is studied in an InGaAs quantum well. Anomalous magnetoresistance is measured and described theoretically in fields perpendicular, tilted and parallel to the quantum well plane. Spin and phase relaxation times are found as functions of temperature and parallel field. It is demonstrated that spin dephasing is due to the Dresselhaus spin-orbit interaction. The values of electron spin splittings and spin relaxation times are found in the wide range of 2D density. Application of in-plane field is shown to destroy weak antilocalization due to competition of Zeeman and microroughness effects. Their relative contributions are separated, and the values of the in-plane electron g-factor and characteristic size of interface imperfections are found.Comment: 8 pages, 8 figure

Evidence of blocking effect on carrier trapping process by necking region in very narrow AlGaAs/GaAs V-grooved quantum wire structure

Transient band-gaprenormalization (BGR) effects are investigated in AlGaAs/GaAs V-grooved quantum structures. The temperature-dependent transient BGR effects in the sidewall quantum well (SQWL) provide direct evidence of the existence of the blocking effect by the necking region barrier on the carrier trapping process. These effects provide a useful method to show the existence of the necking region, particularly for very thin SQWL structures. The temperature-dependent lifetimes of the SQWL and quantum wire (QWR) provide further proof of the carrier trapping process from the SQWL to the QWR.This work was supported in part by a grant from the Academic Frontier Promotion Project of Monbusho, Shanghai ‘‘QiMingXing’’ Fund No. 98QA14004, the State Key Program for Basic Research of China, and the AusAID through IDP Education Australia under Australia-China Institutional Links Program

Effect of intersubband scattering on weak localization in 2D systems

The theory of weak localization is generalized for multilevel 2D systems taking into account intersubband scattering. It is shown that weak intersubband scattering which is negligible in a classical transport, affects strongly the weak-localization correction to conductivity. The anomalous magnetoresistance is calculated in the whole range of classically low magnetic fields. This correction to conductivity is shown to depend strongly on the ratios of occupied level concentrations. It is demonstrated that at relatively low population of the excited subband, it is necessary to use the present theory because the high-field limit asimptotics is shown to be achieved only in classical magnetic fields.Comment: 18 pages, 4 figures. Accepted to Phys. Rev. B 6

Structure of ll- VI Lattice Mismatched Epilayers used for Blue-Green Lasers for Underwater Communication

Critical thickness (hc) is calculated for capped and uncapped lattice mismatched II-VIsemiconductor epilayers. Both the old equilibrium theory and the improved theory have been used.The calculated values are compared with the experimental data on epilayers of several II-VIsemiconductors and alloys. The observed values of hc are larger than the calculated values. Howeverthe discrepancy is much smaller than that found in InGaAs/GaAs and GeSilSi layers. Moreover ascompared to InGaAs/GaA.s:a nd GeSilSi layers, the experimental data show a much smaller scatter andcan be fitted with one curve. Strain relaxation in layers with thickness h > hc is also calculated. Strainrelaxation in ZnSe layers grown on (100) GaAs shows good agreement with the equilibrium theory. Inother cases the observed relaxation is sluggish, the residual strain is larger than its calculated value.Thick highly mismatched layers behave differently. The residual strain agrees with theory anddislocations are distributed periodically, A model to interpret these observations is suggested.Implications of this study on the stability of 11V- I strained layers are discussed