Employing the Anderson impurity model, we study tunneling properties through an ideal quantum dot near the conductance minima. Considering the Coulomb blockade and the quantum confinement on an equal footing, we have obtained current contributions from various types of tunneling processes; inelastic cotunneling, elastic cotunneling, and resonant tunneling of thermally activated electrons. We ha...

We present an experimental demonstration of a latch in a clocked quantum-dot cellular automata ~QCA! device. The device consists of three floating micron-size metal dots, connected in series by multiple tunnel junctions and controlled by capacitively coupled gates. The middle dot acts as an adjustable barrier to control single-electron tunneling between end dots. The position of a switching ele...

objective(s):  the field of nanotechnology is rapidly expanding .the development quantum dots quantum dot (qds), show great promise for treatment and diagnosis of cancer and targeted drug delivery little data on the toxicity of qds, especially for in vivo applications, are available. as a result, concerns exist over their toxicity for in vivo applications. then, cytotoxic effects of cadmium sel...

We propose a genuinely temperature-insensitive quantum dot (QD) laser. Our approach is based on direct injection of carriers into the QDs, resulting in a strong depletion of minority carriers in the regions outside the QDs. Recombination in these regions, which is the dominant source of the temperature dependence, is thereby suppressed, raising the characteristic temperature 0 above 1500 K. Sti...

We demonstrate that quantum dot microdisk lasers are able to operate under continuous wave current injection at 100 o C. We also present a novel method for increasing a side mode suppression ratio in microdisk lasers.

– We study entanglement of charge qubits in a vertical tunnel-coupled double quantum dot containing two interacting electrons. Exact diagonalization is used to compute the negativity characterizing entanglement. We find that entanglement can be efficiently generated and controlled by sidegate voltages, and describe how it can be detected. For large enough tunnel coupling, the negativity shows a...

In this paper we consider electromagnetic field quantization in the presence of a dispersive and absorbing semiconductor quantum dot. By using macroscopic approach and Green's function method, quantization of electromagnetic field is investigated. Interaction of a two-level atom , which is doped in a semiconductor quantum dot, with the quantized field is considered and its spontaneous emission ...