In this paper, we investigate variation of the wavelength, intensity and polarization of the self-assembled InAs/GaAs quantum dots emission by microphotoluminescence spectroscopy at the liquid helium temperature. The microcavity wafer sample is grown by molecular beam epitaxy (MBE) and chemically etched into the micropillar structure (with elliptical cross section - long and short axis 2µm×1.5µ...

Nonblinking excitonic emission from near-infrared and type-II nanocrystal quantum dots (NQDs) is reported for the first time. To realize this unusual degree of stability at the single-dot level, novel InP/CdS core/shell NQDs were synthesized for a range of shell thicknesses (~1-11 monolayers of CdS). Ensemble spectroscopy measurements (photoluminescence peak position and radiative lifetimes) an...

Density functional calculations are performed to study the electronic structure of recently proposed graphene/graphane based core/shell quantum dots, which have a type I band alignment and exhibit quantized carrier energy levels. Strong confinement is robust with shell thickness. The bandgap, band offset, and the number of confined carrier orbitals with different size and geometry are determine...

We demonstrate experimentally that noncollinear intrinsic spin-orbit magnetic fields can be realized in a curved carbon nanotube two-segment device. Each segment, analyzed in the quantum dot regime, shows near fourfold degenerate shell structure allowing for identification of the spin-orbit coupling and the angle between the two segments. Furthermore, we determine the four unique spin direction...

In this paper, the nonlinear rate equations governing a quantum dot laser isused to simulate the transient as well as the steady-state behaviors of the laser.Computation results show that the rate equations are capable of simulating true behaviorof a quantum dot laser. Then, the pump rates of the rate equations (which show indirectelectrical pumping of the quantum dots through a wetting layer) ...

Biomineralization utilizes biological systems to synthesize functional inorganic materials for application in diverse fields. In the current work, we enable biomineralization of quantum confined PbS and PbS–CdS core–shell nanocrystals and demonstrate their application in quantum dot sensitized solar cells (QDSSCs). An engineered strain of Stenotrophomonas maltophilia is utilized to generate a c...

We report on the formation of Ge/Si quantum dots with core/shell structure that are arranged in a three-dimensional body centered tetragonal quantum dot lattice in an amorphous alumina matrix. The material is prepared by magnetron sputtering deposition of Al2O3/Ge/Si multilayer. The inversion of Ge and Si in the deposition sequence results in the formation of thin Si/Ge layers instead of the do...

In this overview paper, we present low-temperature electronic transport measurements of carbon nanotube quantum dots with a back gate. In a semiconducting tube, charge carriers could be completely depleted. The addition energy and the excitation spectrum have been studied as a function of the number of charges (electrons or holes), one by one. We observe electron–hole symmetry, which is a direc...

The electronic conductance at zero temperature through a quantum wire with side-connected asymmetric quantum ring (as a scatter system) is theoretically studied using the non-interacting Hamiltonian Anderson tunneling method. In this paper we concentrate on the configuration of the quantum dot rings. We show that the asymmetric structure of QD-scatter system strongly influences the amplitude an...