Monolayered MoSe2 is a promising new material to investigate advanced light-matter coupling as it hosts stable and robust excitons with comparably narrow optical resonances. In this work, we the evolution of lowest lying excitonic transition, so-called A-valley exciton, temperature. We find strong, phonon-induced temperature broadening resonance, more importantly, reduction oscillator strength for increased temperatures. Based on these experimentally extracted, dependent parameters, apply...

The authors investigate theoretically and experimentally epitaxial nanostructures offering a full range of confinement regimes for excitons due to controlled cross-sectional sizes strong variation in the elongation nanosize objects - from through intermediate weak confinement. It is demonstrated that symmetry breaking leads significantly slower recombination one bright states excitonic fine structure. respective components are detected time-resolved decays unpolarized photoluminescence,which...

We report on the experimental demonstration of triggered single-photon emission at telecom O-band from In(Ga)As/GaAs quantum dots (QDs) grown by metal-organic vapor-phase epitaxy. Micro-photoluminescence excitation experiments allowed us to identify p-shell excitonic states in agreement with high photoluminescence ensemble QDs. Hereby we drive an O-band-emitting GaAs-based QD into get a single photon source purity. Applying pulsed resonant results strong suppression multiphoton events...

The optical and structural properties of a new kind InAs/InGaAlAs/InP quantum dot (QD)-like objects grown by molecular beam epitaxy have been investigated. These nanostructures were found to significantly more symmetrical shapes compared the commonly obtained dash-like geometries typical this material system. enhanced symmetry has achieved due use an As2 source consequent shorter migration length indium atoms. Structural studies based on combination scanning transmission electron microscopy...

The influence of acoustic phonons on the emission spectra quantum dashes (QDashes), that are quasi-zero-dimensional epitaxial nanostructures with significant shape anisotropy, is investigated both experimentally and theoretically. Photoluminescence (PL) single InAs/InGaAlAs/InP (001) QDashes exhibit sidebands main peak, clearly indicating contribution phonon-assisted to exciton luminescence, which dominates PL line at higher temperatures (between 50 100 K, usually). By utilizing independent...

We investigated the neutral and charged exciton fine structure in single InAs/InGaAlAs/InP quantum dashes emitting at 1.55 μm using polarization-resolved microphotoluminescence a magnetic field. Inverted spin configuration of horizontally [1–10] vertically [110] polarized transitions has been observed. An in-plane field up to 5 Tesla applied tailor structure, eventually reduce splitting bright states down zero. This inverted observed for all excitons, making it characteristic feature this...

We present a detailed experimental optical study supported by theoretical modeling of $\mathrm{In}\mathrm{As}$ quantum dots (QDs) embedded in an $(\mathrm{In},\phantom{\rule{-1.5pt}{0ex}}\mathrm{Al},\phantom{\rule{-1.5pt}{0ex}}\mathrm{Ga})\mathrm{As}$ barrier lattice matched to $\mathrm{In}\mathrm{P}$(001) grown with the use ripening step molecular beam epitaxy. The method leads growth in-plane symmetric QDs low surface density, characterized multimodal size distribution resulting spectrally...

We have investigated optical properties of hybrid two-dimensional-zero-dimensional (2D-0D) tunnel structures containing strongly elongated InAs/InP(001) quantum dots (called dashes), emitting at 1.55 μm. These dashes (QDashes) are separated by a 2.3 nm-width barrier from an InGaAs well (QW), lattice matched to InP. tailored quantum-mechanical coupling between the states confined in QDashes and QW changing thickness. By combining modulation spectroscopy photoluminescence excitation, we...

We demonstrate a non-classical photon emitter at near infrared wavelength based on single (In,Ga)As/GaAs epitaxially grown columnar quantum dot. Charged exciton complexes have been identified in magneto-photoluminescence. Photon auto-correlation histograms from the recombination of trion confined dot exhibit sub-Poissonian statistics with an antibunching dip yielding g(2)(0) values 0.28 and 0.46 temperature 10 80 K, respectively. Our experimental findings allow considering GaAs-based...

The molecular beam epitaxy grown structures are investigated, comprising of InGaAs quantum wells (QW) separated by a thin InGaAlAs barrier from InAs dots (QDs), emitting at 1.55 μm, on an InP substrate. To control the coupling between QW and QD parts thickness is changed, which commands wave function overlap. tuning that parameter allows for study influence potential energy structure states their functions in QDs, changing uncoupled system, where optical response just sum responses two...

The electronic structure of strain-engineered single InGaAs/GaAs quantum dots emitting in the telecommunication O band is probed experimentally by photoluminescence excitation spectroscopy. Observed resonances can be attributed to p-shell states individual dots. determined energy difference between s-shell and shows an inverse dependence on emission energy. experimental data are compared with results confined calculations, where impact size composition investigated structures simulated...

Hereby, we present a study of thermal quenching emission from self-assembled epitaxial highly asymmetric quantum dots in InGaAs/GaAs material system for both ensemble and single dot regime.Pronounced interplay between the intensity wetting layer originated was observed as temperature increased, evidencing thermally activated energy transfer two parts an important role determining optical properties these anisotropic nanostructures.The carrier activation energies have been derived possible...

Hereby we present comprehensive experimental and theoretical study on fundamental optical properties electronic structure of GaAs-based quantum dots grown using metalorganic chemical vapor deposition technique.Substantial redshift emission to the second telecommunication window 1.3 µm is obtained via strain engineering utilizing additional capping layer In0.2Ga0.8As in this context referred as reducing layer.The dot has been experimentally characterized by means photoreflectance spectroscopy...

The InAs/InP quantum dots (QDs) are investigated by time-integrated (PL) and time-resolved photoluminescence (TRPL) experiments. QDs fabricated site-selectively droplet epitaxy technique using block copolymer lithography. estimated surface density is ∼1.5 × 1010 cm−2. PL emission at T=300 K centered 1.5 μm. Below T=250 K, the spectrum shows a fine structure consisting of modes attributed to multimodal size distribution. Temperature-dependent reveals negligible carrier transfer among QDs,...

We investigate double layer InAs/GaAs quantum dots grown in the Stransky-Krastanov mode by molecular beam epitaxy.The sample consists of two layers InAs separated 10 nm thick GaAs layer, where top dot an improved homogeneity is covered InGaAs cap.This configuration has allowed for extension dots' emission to longer wavelengths.We probed carrier transfer between states confined a well composed cap and wetting means photoluminescence excitation photoreflectance spectroscopies.Efficient from...

The issue of quantum mechanical coupling between a semiconductor dot and well is studied in two families GaAs- InP- based structures at cryogenic temperatures. It shown that by tuning the parameters one can strongly disturb 0D-character coupled system ground state, initially located dot. out-coupling either an electron or hole state from confining potential viewed significant elongation photoluminescence decay time constant. Band structure calculations show GaAs-based its remains isolated...

The lateral interdot coupling is investigated in high density (∼10 cm−2 ) self-assembled InAs quantum dots (QDs) grown on an InP substrate. Two types of structures are selected for this study, which QDs embedded into InAlAs matrix, forming nearly twice stronger confinement electron and a hole than expected InAlGaAs counterpart. Resonantly injected low carrier population these families gives very different spectral temporal response the temperature range 5-30 K. While InAs/InAlGaAs show...

Lasers, light-emitting diodes, and other optoelectronic devices employing $\mathrm{In}\mathrm{As}$/$\mathrm{In}\mathrm{P}$ quantum dots (QDs) instead of wells (QWs) as their active parts benefit from the quasi-zero-dimensional (0D) density states while maintaining emission at communication-relevant range $1.55\phantom{\rule{0.2em}{0ex}}\ensuremath{\mu}\mathrm{m}$. However, for certain application purposes, substitution QWs with QDs is advantageous only if can either be treated isolated...

There are presented optical properties of strongly in-plane elongated nanostructures the so called quantum dashes made in InAs/InP material system by molecular beam epitaxy. They have been investigated systematically a spectroscopic manner on both entire ensemble and single dash level. Their discussed with respect to fundamental electronic as polarization emission corresponding driving factors, exciton fine structure splitting, biexciton binding energy, characteristic lifetimes ratio...

We present a detailed experimental optical study supported by theoretical modeling of InAs quantum dots (QDs) embedded in an InAlGaAs barrier lattice-matched to InP(001) grown with the use ripening step molecular beam epitaxy. The method leads growth in-plane symmetric QDs low surface density, characterized multimodal size distribution resulting spectrally broad emission range $1.4-2.0$ $\mu$m, essential for many near-infrared photonic applications. find that, contrast InAs/InP system,...