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A theoretical investigation has been made of the magnetoplasmon excitations in a quasi-one-dimensional electron system composed of vertically stacked, self-assembled InAs/GaAs quantum dots. The smaller length scales involved in the experiments impel us to consider a perfectly periodic system of two-dimensionally confined InAs quantum dot layers separated by GaAs spacers. Subsequent system is subjected to a two-dimensional confining (harmonic) potential in the $x$–$y$ plane and an applied magnetic field (B) in the symmetric gauge. This scheme defines virtually a system of quantum wire comprised of vertically stacked quantum dots (VSQD). We derive and discuss the Dyson equation, the generalized (nonlocal and dynamic) dielectric function, and the inverse dielectric function for investigating the single-particle and collective (magnetoplasmon) excitations within the framework of (full) random-phase approximation (RPA). As an application, we study the influence of the confinement potential and the magnetic field on the component eigenfunctions, the density of states (DOS), the Fermi energy, the collective excitations, and the inverse dielectric functions. How the B-dependence of DOS validate the VSQD mimicking the realistic quantum wires, the Fermi energy oscillates as a function of the Bloch vector, the intersubband single-particle continuum bifurcates at the origin, a collective excitation emerges and propagates within the gap of the split single-particle continuum, and the alteration in the well- and barrier-widths allows to customize the excitation spectrum in the desired energy range are some of the remarkable features of this investigation. These findings demonstrate, for the very first time, the significance of investigating the system of VSQD subjected to a quantizing magnetic field. Given the edge over the planar quantum dots and the foreseen applications in the single-electron devices and quantum computation, investigating the system of VSQD is deemed vital. The results suggest exploiting magnetoplasmon qubits to be a potential option for implementing the solemn idea of quantum state transfer in devising quantum gates for the quantum computation and quantum communication networks.

A property of central interest for theoretical study of nanoconfined fluids is the density distribution of molecules. The density profile of the hard-sphere fluids confined within nanoslit pores is a key quantity for understanding the configurational behavior of confined real molecules. In this report, we produce the density profile of the hard-sphere fluid confined within nanoslit pores using the fundamental-measure density-functional theory (FM-DFT). FM-DFT is a powerful approach to studying the structure and the phase behavior of nanoconfined fluids. We report the computational procedure and the calculated data for nanoslits with different widths and for a wide range of hard-sphere fluid densities. The high accuracy of the resulting density profiles and optimum grid-size values in numerical integration are verified. The data reveal a number of interesting features of hard spheres in nanoslits, which are different from the bulk hard-sphere systems. These data are also useful for a variety of purposes, including obtaining the shear stress, thermal conductivity, adsorption, solvation forces, free volume and prediction of phase transitions.

Sleeping sickness (causal agent, Trypanosoma sp. parasite) causes huge morbidity and mortality in Africa (both human and livestock) in particular and zoo animals worldwide. Three of the four currently approved drugs (Pentamidine, Melarsoprol, Eflornithine, and Nifurtimox) were developed over 50 years ago. Current therapies are unsatisfactory due to unacceptable level of side effects. Pentamidine, an aromatic diamidine, safest so far, inhibits mitochondrial enzymes. Furthermore, it is effective only in early stages of infections and not on the later stage. Melarsoprol, practically insoluble in water, is very toxic and it is given intravenously (i.v.) for later stage infections only. Other drugs like eflornithine and nitfurtimox are also unsatisfactory for various reasons. Human serum derived high-density lipoprotein (HDL; not mouse or any other mammalian HDL) shows trypanolytic effect in vitro and in vivo on T. brucei. But the mechanism of action of human HDL is far from clear. In the absence of novel drug leads, nanodrugs might be valid options as nanoparticles show better accessibility to cells, supramolecular interactions due to enormous increase in surface area to volume ratio, altered partition coefficient, etc. Surface-modified hydrophobic microsilica (FS), mixture of micro- and nanosilica (Dsethvasan) and nanosilica (AL) were characterized by UV–Vis, DLS, SEM, EDAX, AFM, and XRD. Trypanosoma evansi collected from infected horses were injected in mice. Control infected mouse (n = 30) showed 100% mortality within 72±24 h of injection. Dsethvasan-treated mice (n = 30) survived for 192±24 h. FS-treated mice (n = 30) survived for 120±24 h but the AL-treated mice (n = 30) died within 72±24 h of inoculation like infected control. Hydrophobic Dsethvasan which consists of pure amorphous forms of micro- and nanosilica works better than FS (AL is not at all effective). Therefore, micro- and nanomixture of amorphous silica is best suited for treating Trypanosoma infection in mice. The possible role of ratio of higher to lower size class has been discussed.

We review the formulation of gauge fields in terms of the frame of reference as well as the space in which the frame is defined. We highlighted some recent applications of gauge physics in the momentum space — in the modern fields of the spin Hall effect, the magnon Hall, the optical Magnus and the graphene valley Hall. General procedures of gauge transformation which lead to the construction of the gauge curvature and the equations of motion (EOM) are outlined. Central to this review is our intention to illustrate the impact of gauge physics on the past and future development of many new research fields emerging out of condensed matter physics, particularly in quantum nanosciences and nanoelectronics.