Direct three-colour fluorescence cross-correlation spectroscopy can reveal interactions between three fluorescently labelled biomolecules, giving insight toward the complex events that constitute signal transduction pathways. Here we provide the optical and theoretical basis for this technology and demonstrate its ability to detect specific biological associations between nanoparticle-labelled DNA molecules.

A multi-scale model is presented that captures the experimentally observed behviour of electroluminescence (EL) in carbon nanotube field-effect transistors (CNFETs) under ambipolar bias conditions, namely variations in mobile EL intensity, localized EL at a contact, and localized EL at a charge defect. A full, quantum mechanical approach is used to describe tunneling and thermionic emission at the contacts, and the drift-diffusion equations, with a field dependent mobility, are used for transport in the long devices (CN length ≥ 10µm). We find that contactlocalized EL is only present when the height of the Schottky barrier at the ends of the CN favours the injection of one type of carrier. Charge defects on the CN surface also lead to localized EL, which is present only under certain bias conditions.

No abstract

The rapidly growing field of integrated photonic quantum computing has recently seen enormous breakthroughs, with integrated photonic devices capable of generating highly entangled states of photons on-chip. To scale these devices, simulation tools that model realistic sources and manufacturing imperfections are required when designing quantum building blocks that meet fidelity requirements and fault tolerance thresholds. To address this, we introduce a quantum circuit solver capable of calculating the heralded source biphoton wavefunction and corresponding frequency domain response of photonic integrated circuits in the Fock basis, yielding the fidelity of the output state and probability of success for a given measurement outcome.

In the modeling of carbon nanotube field-effect transistors, non-physical boundary conditions are often employed at the borders of the simulation space. This paper investigates the consequences of imposing these boundary conditions on common geometries, and proposes solutions which reduce the error without compromising simulation efficiency.

No abstract

No abstract

The relentless need for higher bandwidth, lower power and lower cost data communications has driven tremendous innovation in integrated photonics in recent years. This innovation has been supported by state-of-the-art electronic-photonic design automation (EPDA) workflows, which enable process design kit (PDK) centred schematic driven design and layout, as well as statistically enabled electro-optical simulation. In addition, custom components can be introduced and optimized for a specific foundry process using advanced methods such as photonic inverse design and machine learning. While much of the innovation has been motivated by data communications, it has enabled a variety of different applications such as sensing, integrated LiDAR and quantum information technologies. We discuss the latest innovations in EPDA workflows and show how a silicon photonic ring-based wavelength demultiplexing (WDM) system can be easily designed, simulated and implemented. In addition, we discuss the extension of these workflows to support the design and simulation of quantum photonic devices, enabling designers to consider the effects of realistic sources and manufacturing imperfections when designing quantum building blocks to meet specific fidelity and fault tolerance thresholds.