In the presence of gratuitous inducers, the lac operon of Escherichia coli exhibits bistability. Most models in the literature assume that the inducer enters the cell via the carrier (permease), and exits by a diffusion-like process. The diffusive influx and carrier efflux are neglected. However, analysis of the data shows that in non-induced cells, the diffusive influx is comparable to the car...

Conductivity data of the xAgI(1 - x)AgPO(3) system (0 ≤ x ≤ 0.5) were collected in the liquid and glassy states. The difference in the dependence of ionic conductivity on temperature below and above their glass transition temperatures (T(g)) is interpreted by a discontinuity in the charge carrier's mobility mechanisms. Charge carrier displacement occurs through an activated mechanism below T(g)...

Photoinduced carrier dynamics in a sequence of InGaN/GaN multiple quantum wells (MQWs) are studied by employing steady state and ultrafast spectroscopy at room temperature. Time-resolved photoluminescence (PL) measured short carrier lifetimes of ,140 ps at room temperature. Steady state differential transmission was used to measure the in-well field screening due to the photoinjected carriers. ...

We investigate theoretically the spin-spin interaction of two-electrons in vertically coupled QDs as a function of the angle between magnetic field and growth axis. Our numerical approach is based on a real-space description of single-particle states in realistic samples and exact diagonalization of carrier-carrier Coulomb interaction. In particular, the effect of the in-plane field component o...

We consider a nonlinear lattice of the Klein—Gordon type analysing envelope solitons created on a standing carrier wave. In particular, we show that nonlinear wavesofsuch a kind are described by a system of two coupled nonlinear Schrodinger equations and we find a new class of its solutions which describe bound states of two dark-profile solitons. As particular cases, this solution includes non...

We report on the optical conductivity of the structurally ordered icosahedral quasicrystal A17QPd2QRe IQ and the crystal A12Ru obtained from the reflectance measured over a wide frequency range. Our results show that both the crystal and the quasicrystal are semiconductors and have quite similar band structure. The major difference between the two materials arises from the localization of the e...

1. Demsar,I,2,3 V. V. Kabanov,I,3 A: S. Alexandrov,4 H. 1. Lee,5 E. D. Bauer,5 1. L. Sarrao,5 and A. 1. Taylor5 Iphysics Department and Zukunftskolleg, University of Konstanz, D-78457 Konstanz, Germany 2Center for Applied Photonics, University of Konstanz, D-78457 Konstanz, Germany 3Complex Matter Department, lozef Stefan Institute, SI-lOOO Ljubljana, Slovenia 4Department of Physics, Loughborou...

We used a bilayer field effect transistor (FET) consisting of a thin PbS nanocrystals (NCs) film interfaced with vacuum-deposited pentacene to probe trap states in NCs. We interpret the observed threshold voltage shift in context of charge carrier trapping by PbS NCs and relate the magnitude of the threshold voltage shift to the number of trapped carriers. We explored a series of NC surface lig...

This chapter is devoted to the recent theoretical results on the optical quantum control over charges confined in quantum dots under influence of phonons. We show that lattice relaxation processes lead to decoherence of the confined carrier states. The theoretical approach leading to a uniform, compact description of the phonon impact on carrier dynamics, perturbative in phonon couplings but ap...

We report on the effect of oxygen disorder in the CuO chains on the superconducting properties of oxygen depleted YBa2Cu3Ox(YBCO). While moderate disorder, induced thermally, depresses the critical temperature as a result of a reduced carrier concentration, strong oxygen disorder and chain fragmentation induced by low energy ~80 keV! He irradiation suppresses the critical temperature beyond the...