Top 1010 Videos

P01–Design of a computer-generated waveguide hologram for integrated free space sensing

Liu T., Jiao Y., Bente E.

In this work we present a design of a computer generated waveguide hologram coupler with an ultra-long working distance and wavelength multiplexing in the near infrared. An approximation method to compute the scalar field from a detour phase hologram is presented. The accuracy is comparable to FDTD but it is achieved much faster. Coupling efficiency […]

N02–Wave-function engineering in (In,Ga)As/(In,Al)As core/shell nanowires

Marquardt O., Geelhaar L., Brandt O.

 We study the electronic properties of In0.53Ga0.47As/InxAl1–xAs core/shell nanowires for light emission in the telecommunication range. In particular, we systematically investigate the influence of the In content x of the InxAl1–xAs shell and the diameter d of the In0.53Ga0.47As core on strain distribution, transition energies, and the character of the hole wave function. We show […]

N03–Numerical and Experimental Characterization of Chirped Quantum Dot-based Semiconductor Optical Amplifiers

Forrest A. F., Cataluna M. A., Krakowski M., Giannuzzi G., Bardella P.

We present a model for the description of the dynamical behavior of Quantum Dot (QD) based Semiconductor Optical Amplifiers (SOAs) under injection of optical pulses. The model uses a Time Domain Traveling Wave (TDTW) approach to describe the optical field in the amplifier, and allows us to consider chirped QD materials by the inclusion of […]

LED02–Rigorous simulation of photon recycling effects in perovskite solar cells and LEDs

Aeberhard U., Zeder S., Ruhstaller B.

Secondary photogeneration due to reabsorption of internally emitted photons in metal halide perovskites is assessed using a novel dipole emission model that is compatible with detailed balance rates. The model considers the non-uniform local photon density of states of thin film absorbers/emitters consistently in internal and external emission and provides insight into the impact of […]

LD02–GaN-based bipolar cascade laser exceeding 100% differential quantum efficiency

Piprek J., Siekacz M., Muziol G., Skierbiszewski C.

Worldwide research efforts have been focusing on quantum efficiency enhancements of GaN-based light emitters. A promising approach is the separation of multiple active regions by tunnel junctions, enabling electron-hole pairs to generate more than one photon. Utilizing advanced numerical device simulation, we here analyze internal physics and performance limitations of such InGaN/GaN bipolar cascade laser […]

LD03–Thermal and optical simulation of InP on Si nanocavity lasers

Wen P., Tiwari P., Moselund K. E., Gotsmann B.

Accurate prediction of thermal effects is important for scaled photonic devices as excessive heating may lead to device failure. This paper addresses numerical modeling of thermal properties of InP nanocavity lasers on Si combined with optical simulations in Lumerical and lasing threshold measurements. Different geometries with diameters ranging from 200 nm to 2 µm are […]

LD04–A multiscale approach for BTJ-VCSEL electro-optical analysis

Gullino A., Pecora S., Tibaldi A., Bertazzi F., Goano M., Debernardi P.

This paper presents a theoretical comparison of the electro-optical characteristics of 850 nm GaAs/AlGaAs pinand BTJ-based VCSELs. The calculations are based on a drift-diffusion model coupled with a NEGF formalism, able to model accurately the tunneling across the TJ. The resulting LIV characteristics demonstrate promising improvements, at both 25 and 80 ◦C, enabled by TJ […]

P02–Quantum Information Interface on a Photonic Crystal Chip

Mertin P., Witzigmann B.

Quantum systems for information processing rely on the distribution of quantum information in a network. Lanthanide complexes coupled to an optical cavity can act as an interface between a stationary and a flying QuBit. Here we show that in such a system the stationary quantum information can be mapped onto a photon, paving the way […]

LED01–Effect of Inhomogeneous Broadening in Deep Ultraviolet Light Emitting Diodes

Roemer F., Witzigmann B.

Due to their small dimensions deep ultraviolet (DUV) light emitting diodes (LED) are highly attractive light sources for environmental and medical applications. DUV LEDs generate light in active quantum wells (QW) made of Aluminium Gallium Nitride. The QWs are not lattice matched to the substrate and only few monolayers thick making them susceptible to compound […]