A comprehensive theory of the modulation response of quantum dot (QD) lasers is developed. The factors limiting the modulation bandwidth are identified and the highest possible bandwidth is calculated. The highest bandwidth increases directly with overlap integral of the electron and hole wave functions in a QD, number of QD-layers, and surface density of QDs in a layer, and is inversely propor...

Monolayer black phosphorus (MBP) is an interesting emerging electronic material with a direct band gap and relatively high carrier mobility. In this work we report a theoretical investigation of nonequilibrium spin injection and spin-polarized quantum transport in MBP from ferromagnetic Ni contacts, in two-dimensional magnetic tunneling structures. We investigate physical properties such as the...

Contents 1. Introduction 2. Electronic states in a weakly oblated ellipsoidal quantum dot (impermeable walls). 3. The model of finite deep rectangular ellipsoidal well 4. Strongly oblated ellipsoidal quantum dot 5. Strongly prolated ellipsoidal quantum dot 6. Electronic states in a cylindrical quantum dot having elliptical lens shaped cross section 7. Electronic states in a cylindrical quantum ...

The CMOS transistor has reached the molecular level due to the continuous miniaturization. With devices that small, problems in manufacturing and functionality appear. Since quantum effects become prevalent, technology that would take advantage of them is desirable. One of the proposed novel technologies is the quantum-dot cellular automaton (QCA) [1, 2]. Its basic building block is a QCA cell ...

Like modern microprocessors today, future processors of quantum information may be implemented using all-electrical control of silicon-based devices. A semiconductor spin qubit may be controlled without the use of magnetic fields by using three electrons in three tunnel-coupled quantum dots. Triple dots have previously been implemented in GaAs, but this material suffers from intrinsic nuclear m...

This investigation experimentally demonstrates the dynamic characteristics of quantum dot vertical-cavity surface-emitting lasers (QD VCSEL) without and with light injection. The QD VCSEL is fully doped structure on GaAs substrate and operates in the 1.3 mum optical communication wavelength. The eye diagram, frequency response, and intermodulation distortion are presented. We also demonstrate t...

Abstract Combining external control with long spin lifetime and coherence is a key challenge for solid state qubits. Tunnel coupling electron Fermi reservoir provides robust charge in semiconductor quantum dots, but results undesired relaxation of nuclear spins through mechanisms that lack complete understanding. Here, we unravel the contributions tunnelling-assisted phonon-assisted by systemat...

We show experimentally that polarization mode hopping in quantum dot vertical cavity surface emitting lasers (VCSELs) takes place between nonorthogonal elliptically polarized modes. In contrast to quantum well VCSELs the average dwell time decreases with injection current. This decrease is by 8 orders of magnitude: from seconds to nanoseconds and is achieved without any modifications of the VCS...

Thermal to electric energy conversion with thermophotovoltaics relies on radiation emitted by a hot body, which limits the power per unit area to that of a blackbody. Microgap thermophotovoltaics take advantage of evanescent waves to obtain higher throughput, with the power per unit area limited by the internal blackbody, which is n2 higher. We propose that even higher power per unit area can b...

We report on a method for single-shot readout of spin states in a semiconductor quantum dot that is robust against charge noise and can be used even when the electron temperature exceeds the energy splitting between the states. The spin states are first correlated to different charge states using a spin dependence of the tunnel rates. A subsequent fast measurement of the charge on the dot then ...