It's a Trap: Studying the quantum dot surface on an atomistic scale

Due to their size-dependent properties, high photoluminescence quantum yield and relatively cheap solution-based processing, colloidal quantum dots (QDs) are of great interest for application in optoelectronic devices. However, the efficiency of these devices is often limited by the presence of trap states: localized electronic states that lead...

Surface Reconstructions in II-VI Quantum Dots

Although density functional theory (DFT) calculations have been crucial in our understanding of colloidal quantum dots (QDs), simulations are commonly carried out on QD models that are significantly smaller than those generally found experimentally. While smaller models allow for efficient study of local surface configurations, increasing the...

Spin Qubits in Silicon and Germanium

Quantum computers based on semiconductor quantum dots are proving promising contenders for large scale quantum information processing. In particular, group IV based semiconductor hosts containing an abundance of nuclear spin-zero isotopes have made considerable headway into fulfilling the requirements of a universal quantum computer. Silicon (Si...

Multi-terminal electronic transport in boron nitride encapsulated TiS₃ nanosheets

We have studied electrical transport as a function of carrier density, temperature and bias in multi-terminal devices consisting of hexagonal boron nitride (h-BN) encapsulated titanium trisulfide (TiS₃) sheets. Through the encapsulation with h-BN, we observe metallic behavior and high electron mobilities. Below ∼60 K an increase in...

Metal Halide Perovskite Polycrystalline Films Exhibiting Properties of Single Crystals

Metal halide perovskites are generating enormous excitement for use in solar cells and light-emission applications, but devices still show substantial non-radiative losses. Here, we show that by combining light and atmospheric treatments, we can increase the internal luminescence quantum efficiencies of polycrystalline perovskite films from 1...

A first single-photon avalanche diode fabricated in standard SOI CMOS technology with a full characterization of the device

This paper reports on the first implementation of a single-photon avalanche diode (SPAD) in standard silicon on insulator (SOI) complementary metal-oxide-semiconductor (CMOS) technology. The SPAD is realized in a circular shape, and it is based on a P+/N-well junction along with a P-well guard-ring structure formed by lateral diffusion of two...

Contact-free handling using actively controlled electrostatic levitating fields

In general electric field forces have the distinctive property of being able to mediate forces to virtually any material in a fully non-invasive and contact-free fashion. Based on this property, electrostatic levitation holds great promise for the semiconductor, solar panel, and flat-panel display industry since the handling of (semi)conducting...

Multi signal-domain modeling of solid-state transducers: A theoretical framework based on irreversible thermodynamics mixed finite elements and multigrid

Spontaneous resistance switching and low-frequency noise in quantum point contacts