Waveguide nonlinear-optic devices and integrated semiconductor lasers with appropriate design can perform quantum-optics functions that are potentially useful for R&D of quantum information processing. This paper reports the current status of the work of the authors group in this new subarea "Quantum Photonic Devices", including theoretical background, design and fabrication of quasi-phase matc...

We present an overview of experimental steps taken towards using the spin of a single electron trapped in a semiconductor quantum dot as a spin qubit [Loss and DiVincenzo, Phys. Rev. A 57, 120 (1998)]. Fabrication and characterization of a double quantum dot containing two coupled spins has been achieved, as well as initialization and single-shot read-out of the spin state. The relaxation time ...

The interaction of an electronic spin with its nuclear environment, an issue known as the central spin problem, has been the subject of considerable attention due to its relevance for spin-based quantum computation using semiconductor quantum dots. Independent control of the nuclear spin bath using nuclear magnetic resonance techniques and dynamic nuclear polarization using the central spin its...

The influence of hidden symmetry on two-dimensional excitonic states in semiconductor quantum wells is investigated. It is shown that excitonic states in quantum wells, with the parabolic dispersion law for the electron and hole, and Sommerfeld’s coefficients for excitonic transitions are determined only with the principle quantum number within the framework of two-dimensional Coulomb potential...

Quantum dots laser diodes using the dots-in-a-well (DWELL) structure (InAs dots in an InGaAs quantum wells) have exhibited significant recent progress. With a single InAs dot layer in Inoi5Gao.8sAs quantum well, threshold current densities are as low as 26 A cm2 at 1 .25 xm. Quantum dot laser threshold current densities are now lower than any other reported semiconductor laser. In this work, th...

By analyzing the interaction of a few-cycle laser pulse within an asymmetric semiconductor double quantum well structure, we show that the transient coherence thus produced is strongly dependent on the carrier-envelope-phase (CEP) and significantly enhanced due to the Fano-type interference. A method to determine the CEP is proposed by directly mapping the CEP dependent coherence to the quantum...

We demonstrate the first electrically pumped quantum-dot micro-ring lasers epitaxially grown on (001) silicon. Continuous-wave lasing around 1.3 μm was achieved with ultra-low thresholds as small as 0.6 mA and maximum operation temperatures up to 100°C. OCIS codes: (230.5590) Quantum-well, -wire and -dot devices; (140.5960) Semiconductor lasers; (140.3948) Microcavity devices; (160.3130) Integr...

In this study, our recent research activities on nanophotonic devices with semiconductor quantum nanostructures are reviewed. We have developed a technique for nanofabricating of high-quality and high-density semiconductor quantum dots (QDs). On the basis of this core technology, we have studied next-generation nanophotonic devices fabricated using high-quality QDs, including (1) a high-perform...

incorporate hundreds of millions of semiconductor devices (transistors, diodes, optical devices, etc.). To predict the performance of the VLSI circuits, the current-voltage (I-V) characteristics of the semiconductor device are required. Semiconductor device simulation codes provide a way of predicting I-V curves as device parameters are varied, without having to fabricate the device first. (The...

We explore and demonstrate quantum confinement without walls in metal-clad InAs quantum wells. We observed intersubband absorption from confined states in InAs clad with Al, Sb, Nb, W, Pt, Ag, Au, Ti or In. We found that using this novel method, we can explore the physics and chemistry at the metal–semiconductor interface; reflection, autoionization, well-width fluctuation and interface reactio...