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An active region design based on InGaN / delta-InN quantum well (QW) with AlGaN interlayer (IL) and GaN barriers (delta-structure) is investigated for potential high-efficiency visible light emitters. Numerical simulations demonstrate a large wavelength redshift with a simultaneous increase of the electron-hole wavefunction overlap for the delta-structure as compared to the conventional InGaN QW with AlGaN IL and GaN barriers. Proof of concept experimental growths via the metalorganic chemical vapor deposition demonstrate the effect of the delta-InN insertion into the conventional InGaN-based QW. [ABSTRACT FROM AUTHOR]

Semiconductor quantum dots are currently emerging as one of the most promising sources of non-classical light on which to base future quantum networks. They can generate single photons as well as pairs of entangled photons with unprecedented brightness, indistinguishability, and degree of entanglement. These features have very recently opened up the possibility to perform advanced quantum optics protocols that were previously inaccessible to single quantum emitters. In this work, we report on two experiments that use the non-local properties of entanglement to teleport quantum states: three-photon state teleportation and four-photon entanglement teleportation. We discuss all the experimental results in light of a theoretical model that we develop to account for the non-idealities of the quantum source. The excellent agreement between theory and experiment enables a deep understanding of how each parameter of the source affects the teleportation fidelities and it pinpoints the requirements needed to overcome the classical limits. Finally, our model suggests how to further improve quantum-dot entangled-photon sources for practical quantum networks. [ABSTRACT FROM AUTHOR]

A physics-based compact model of silicon carbide (SiC) junction barrier Schottky diode for circuit simulation is developed in this paper. The semiconductor physics mechanism in SiC, such as temperature-dependent mobility and incomplete ionization, are considered. The detailed device parameters, including drift region concentration, drift thickness, active area, and Schottky barrier height, are modeled. Then, a datasheet-oriented parameter extraction procedure for the device parameters is presented for three kinds of commercial SiC Schottky diodes with junction barrier structure. The model is implemented in the circuit simulator PSpice. In order to verify this model, the Technology Computer-Aided Design Sentaurus simulation is conducted with the device parameters and physical models, which shows a good agreement with the PSpice simulation. [ABSTRACT FROM AUTHOR]

The concept of electric current is fundamental in the study of electrical engineering (EE). Students are often exposed to this concept in their daily lives and early in middle school education. Lower-division university courses are usually limited to the study of passive electronic devices and simple electric circuits. Semiconductor physics is an upper-division course that presents the physics behind semiconductor devices in depth and exposes the students to microscale explanations of different types of current, such as drift and diffusion currents. This paper investigates how third-year college students majoring in EE link microscale and macroscale concepts of current, and what misconceptions they reveal after one quarter of advanced instruction in semiconductor physics. The interviewees were posed a problem, based on a distracting device structure that exposed student difficulties in defining current, charges and doping, and the plotting of current–voltage (I–V) characteristics. For example, some students had the naïve idea that current is the flow of a particular type of charge (i.e., only electrons or only holes) or that there is a “spectrum of doping.” Almost all students drew a one-quadrant coordinate system for the I–V curves, which might imply that students think only about positive voltages. These findings can inform further studies to identify and address misconceptions in the important area of semiconductor device physics. [ABSTRACT FROM PUBLISHER]

Substrate coupling in 3-D-ICs using Cu through silicon vias (TSVs) is a predicament widely documented in recent literature. Yet, discussions remain limited to the electromagnetic framework, such that a complete understanding of noise propagation and absorption is hampered. This letter thoroughly examines these phenomena in the TSVs from the integrated perspectives of semiconductor physics and electromagnetic theory and investigates the noise reduction method using the combination of p \(+\) guard-ring and grounded TSV via 3-D device simulation. [ABSTRACT FROM AUTHOR]