Publications de Elyahou Kapon | EPFL Graph Search

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A novel technique for tuning the strength of quantum confinement in site-controlled semiconductor quantum dots (QDs) is introduced and investigated theoretically and experimentally. The method makes use of controlled local growth rates during metalorganic ...

Vertical-cavity surface-emitting laser (VCSEL)-by-VCSEL optical injection locking to obtain high cutoff frequencies of 1.3-mu m VCSELs is demonstrated. A detailed physical explanation of the underlying mechanism is presented. VCSELs from the same wafer have been used in a master-follower configuration. Two probe stations are used in this experiment to power-up two VCSELs simultaneously. Polarization insensibility of the injection locking is demonstrated and a novel architecture is proposed to achieve cutoff

We review recent results on wafer fused long wavelength VCSELs emitting in the 1310 - 2000 nm range. This technology allows reaching fundamental mode output in excess of 4.5 mW at room temperature and close to 3 mW at 70 degrees C for both the 1310 nm and 1550 nm wavebands-the highest values obtained so far. Emission wavelength can be tuned continuously with current with a tuning range as large as 15 nm. For 2000 nm emission wavelength, room temperature output is similar to 0.5 mW, limited so far by high op

We present 6.1 W of output power from a flip-chip semiconductor disk laser (SDL) emitting in the 1.3 mu m wavelength region. This is the first demonstration of a flip-chip SDL in this wavelength range with output powers that are comparable to those obtaine ...

We report on the growth and optical properties of dense arrays of single GaAs/AlGaAs quantum dot (QD) heterostructures with pitches as small as 300 nm. The samples were grown by organometallic chemical vapor deposition in dense inverted pyramids on {1 1 1}B GaAs substrate pre-patterned using electron beam lithography and wet chemical etching. The growth conditions such as deoxidation and growth temperatures, growth rates, and V/III ratio, had to be chosen quite differently from those employed with micron-si

We report on carrier-induced effects on emission and absorption in forward biased GaAs/AlGaAs V-groove quantum wire (QWR) diodes observed using low-temperature (10 K) photoluminescence (PL), electroluminescence (EL) and PL excitation (PLE) spectroscopy. In the case of simultaneous electron-hole injection we observe a band-gap renormalization (BGR) of at least 5 meV for a carrier density of approximate to 10(6) cm(-1), by comparing high-density EL spectra with low-density PLE spectra. In the case of electron

We use polarization-resolved two-photon microscopy to investigate second harmonic generation (SHG) from individual assemblies of site-controlled nano-pyramidal recess templates covered with silver films. We demonstrate the effect of the surface plasmon pol ...

We demonstrate that the emission characteristics of site-controlled InGaAs/GaAs single quantum dots embedded in photonic crystal slab cavities correspond to single confined excitons coupled to cavity modes, unlike previous reports of similar systems based ...

The effect of surface passivation in BCl3/N-2 inductively coupled plasma reactive-ion etching of GaAs-based photonic crystals (PhCs) was investigated. It is shown that sidewall passivation is crucial for achieving cylindrical, vertical PhC holes, where the ...

Optically-pumped vertical external cavity surface emitting lasers (VECSELs) based on flip-chip gain mirrors emitting at the 1.55-mu m wavelength range are reported. The gain mirrors employ wafer-fused InAlGaAs/InP quantum well heterostructures and GaAs/AlA ...

Optically pumped wafer fused 1310 nm VECSELs have the advantage of high output power and wavelength agility. Gain mirrors in these lasers are formed by direct bonding of InAlGaAs/InP active cavities to Al(Ga) As/GaAs DBRs. We present for the first time Wat ...

We report on time-resolved and steady-state photoluminescence studies of GaAs/AlGaAs V-groove quantum wire structures. Steady-state photoluminescence experiments are performed in the temperature range from 8 to 200 It. We evaluate the relation between photoluminescence excitation and absorption and determine experimentally the optical density in order to analyze the temperature dependence of the photoluminescence spectra. We find that, at a temperature above 60 K, the photoexcited electron-hole pairs reach

In dilute nitride InyGa1-yAs1-xNx alloys, a spatially controlled tuning of the energy gap can be realized by combining the introduction of N atoms-inducing a significant reduction of this parameter-with that of hydrogen atoms, which neutralize the effect o ...

We propose and investigate a new type of photonic crystal (PhC) cavity for integrated quantum photonics, which provides tailored optical modes with both confined and extended spatial components. The structures consist of elongated PhC cavities in which the ...

We report on the observation of negatively- and positively-charged excitons in the photoluminescence spectra of V-groove quantum wires. The. charged exciton binding energy increases with the strength of the quantum confinement. We demonstrate that fluctuat ...

We investigate the embedded interfaces of GaAs/AlGaAs quantum wells grown by metal organic vapor phase epitaxy on slightly (< 1 degrees)-misoriented (001) substrates using selective etching and atomic force microscopy. Depending on the substrate misorienta ...

Two site-controlled quantum dots (QDs) were integrated in a photonic crystal molecule (PCM) formed by L3 nanocavities. A statistical analysis of the coupled cavity modes demonstrated the formation of bonding and anti-bonding delocalized PCM states. Exciton ...

We show that the two-dimensional quantum confined Stark effect in a semiconductor quantum wire can display novel behaviour, i.e. wave function splitting and cascading. No analog to these phenomena can be found in bulk material or quantum wells. The consequences of these effects on Stark shifts, oscillator strengths and electroabsorption spectra are explored numerically using k.p theory. A non-trivial prediction of our model is that, for the case of hole wave function splitting, the cascading of the ladder o

Digital chemical etching is used to trim the output mirror thickness of wafer-fused VCSELs emitting at a wavelength near 1.5 mu m. The fine control of the photon cavity lifetime thus achieved is employed to extract important device parameters and optimize ...

We demonstrate engineering of carrier states in the conduction band (CB) and valence band (VB) of site-controlled InGaAs/GaAs quantum dots (QDs) grown into pyramidal recesses, by controlling their shape, size, and composition. QDs with CB level separation ranging from ∼15 to 70 meV are obtained, useful in applications based on intraband transitions, e.g., QD photodetectors and QD cascade lasers. Moreover, by varying the aspect ratio and composition of the QDs we are able to switch the polarization of the do

Elyahou Kapon

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Mechanisms of Quantum Dot Energy Engineering by Metalorganic Vapor Phase Epitaxy on Patterned Nonplanar Substrates

Long Wavelength VCSL-by-VCSEL Optical Injection Locking

Recent Developments in Long Wavelength VCSELs Based on Localized Wafer Fusion

High-power flip-chip semiconductor disk laser in the 1.3 μm wavelength band

Growth and Optical Characterization of Dense Arrays of Site-Controlled Quantum Dots Grown in Inverted Pyramids

Carrier-induced effects on absorption and emission in V-groove quantum wire diodes

Effects of surface plasmon polariton-mediated interactions on second harmonic generation from assemblies of pyramidal metallic nano-cavities

Phonon-Mediated Coupling of InGaAs/GaAs Quantum-Dot Excitons to Photonic Crystal Cavities

Effect of sidewall passivation in BCl3/N2 inductively coupled plasma etching of two-dimensional GaAs photonic crystals

1.55-mu m wavelength wafer-fused OP-VECSELs in flip-chip configuration

Wafer-fused VECSELs emitting in the 1310 nm waveband

Photoluminescence study of V-groove quantum wires: The influence of disorder on the optical spectra and the carrier thermalization

Selective Effects of the Host Matrix in Hydrogenated InGaAsN Alloys: Toward an Integrated Matrix/Defect Engineering Paradigm

Tilted-potential photonic crystal cavities for integrated quantum photonics

Charged excitons in modulation-doped quantum wires

Correlation between optical properties and interfaces morphology of GaAs/AlGaAs quantum wells

Site-controlled quantum dots coupled to a photonic crystal molecule

Quantum confined Stark effect in quantum wires: Wave function splitting and cascading

Control of cavity lifetime of 1.5 mu m wafer-fused VCSELs by digital mirror trimming

Engineering conduction and valence band states in site-controlled pyramidal quantum dots