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A quantum dot is a semiconductor nanostructure that confines the motion of conduction band electrons and valence band holes in all three spatial directions, thus creating fully discrete energy levels. The confinement in the InAs/GaAs material system is gen ...
Photonic crystal (PC) cavities enable localization of light into volumes (V) below a cubic optical wavelength (smaller than any other types of optical resonators) with high quality (Q) factors [1]. This permits a strong interaction of light and matter, whi ...
A large number of characterization tools for semiconductor based heterostructures are available nowadays. Most of these techniques deliver high temporal resolution (down to hundreds of femtoseconds) or good spatial resolution (down to sub nanometer resolut ...
Efficiency and speed of photonic crystal lasers are improved by passivating InGaAs/GaAs membranes using (NH(4))S treatment. Lasers show five-fold reduction in nonradiative surface recombination rate, resulting in four-fold reduction in threshold and room-t ...
We study the dynamics of the charged and neutral excitons in a modulation-doped GaAs quantum well by time-resolved photoluminescence under a resonant excitation. The radiative lifetime of the charged exciton is found to be surprisingly short, 60 ps. This t ...
Single photon sources have recently attracted significant interest for their potential role in the future applications of quantum cryptography, and in the longer term, quantum computing. Among the different types of single photon emitters, semiconductor qu ...
We report direct evidence of enhanced spontaneous emission in a photonic-crystal (PhC) light-emitting diode. The device consists of p-i-n heterojunction embedded in a suspended membrane, comprising a layer of self-assembled quantum dots. Current is injecte ...
In this letter, we take advantage of the high coefficient of thermal expansion (CTE) of a chemically amplified, epoxy-based negative polymer (SU-8) to define a low-power consumption polymeric variable optical attenuator that combines the working principles ...
Photonic crystals are periodic dielectric structures, where the periodicity varies on the wavelength scale. Analogous to electrons in semiconductors, the photon propagation can be described using a band structure in which transmission bands are separated b ...
We have recently demonstrated a number of functional photonic crystals devices and circuits, including an ultrafast, room-temperature, low threshold, nanocavity laser with the direct modulation speed approaching 1THz, an all-optical switch controlled with ...
