Polarized and Bright Telecom C-Band Single-Photon Source from InP-Based Quantum Dots Coupled to Elliptical Bragg Gratings.

Bright, polarized, and high-purity single-photon sources in telecom wavelengths are crucial components in long-distance quantum communication, optical quantum computation, and quantum networks. Semiconductor InAs/InP quantum dots (QDs) combined with photonic cavities provide a competitive path, leading to optimal single-photon sources in this range. Here, we demonstrate a bright and polarized single-photon source operating in the telecom C-band based on an elliptical Bragg grating (EBG) cavity.

Luminescent Properties of Phosphonate Ester-Supported Neodymium(III) Nitrate and Chloride Complexes.

This study examines the synthesis of two geminal bisphosphonate ester-supported Ln complexes [Ln()(NO)] (Ln = Nd (), La ()) and optical properties of the neodymium(III) complex. These results are compared to known mono-phosphonate ester-based Nd complexes [Nd(/)X] (X = NO, n = 1; Cl, n = 2) (-). The optical properties of Nd compounds are determined by micro-photoluminescence (µ-PL) spectroscopy which reveals three characteristic metal-centered emission bands in the NIR region related to transitions from F excited state.

Temperature dependence of refractive indices of AlGaAs and InAlGaAs in the telecommunication spectral range.

In this work, we determine the temperature dependence of refractive indices of InAlGaAs and AlGaAs semiconductor alloys at telecommunication wavelengths in the range from room temperature down to 10 K. For that, we measure the temperature-dependent reflectance of two structures: with an AlGaAs/GaAs distributed Bragg reflector (DBR) designed for 1.3 µm and with an InAlGaAs/InP DBR designed for 1.

Spin memory effect in charged single telecom quantum dots.

Single InP-based quantum dots emitting in the third telecom window are probed quasi-resonantly in polarization-resolved microphotoluminescence experiments. For charged quantum dots we observe negative circular polarization being a fingerprint of the optical spin writing of the carriers within the quantum dots. The investigated quantum dots have a very dense ladder of excited states providing relatively easy quasi-resonant optical excitation, and together with telecom wavelengths emission they bring quantum gates and memories closer to compatibility with fiber-optic communication.

Spin memory effect in charged single telecom quantum dots: erratum.

This erratum corrects the value of the wetting layer thickness provided in our Article [Opt. Express29, 34024 (2021)10.1364/OE.

Azido-Functionalized Aromatic Phosphonate Esters in POSS-Cage-Supported Lanthanide Ion (Ln = La, Nd, Dy, Er) Coordination.

Within this work, a modified preparation of diethyl 4-azidobenzylphosphonate () is presented and the family of 4- or 4'-azido-substituted aromatic phosphonate esters is increased by three new ligand platforms: diisopropyl 4-azidobenzylphosphonate (), diisopropyl ((4'-azido-[1,1'-biphenyl]-4-yl)methyl)phosphonate (), and diisopropyl 4-azido-2,3,5,6-tetrafluorobenzylphosphonate (), which exhibit an anomalous splitting of the N stretching vibrations. Subsequent coordination to the generated POSS (polyhedral oligomeric silsesquioxane)-cage-supported lanthanide precursors [(Ln{POSS})(THF)] (-) (Ln = La, Nd, Dy, Er; R = Bu, Ph; = 0, 1) yields complexes of the general formula [Ln{POSS}(-)()(THF)] (-) ( = 2, 3; = 0, 1; = 0-2) retaining the azide unit for future semiconductor surface immobilization. Because the latter compounds are mostly oils or viscous waxes, preliminary solution-state structure elucidations via DOSY-ECC-MW estimations have been carried out which are in accordance with H NMR integral ratios as well as solid-state structures, where available.

Magneto-Optical Characterization of Trions in Symmetric InP-Based Quantum Dots for Quantum Communication Applications.

Magneto-optical parameters of trions in novel large and symmetric InP-based quantum dots, uncommon for molecular beam epitaxy-grown nanostructures, with emission in the third telecom window, are measured in Voigt and Faraday configurations of an external magnetic field. The diamagnetic coefficients are found to be in the range of 1.5-4 μeV/T, and 8-15 μeV/T, respectively out-of-plane and in-plane of the dots.

Functionalised phosphonate ester supported lanthanide (Ln = La, Nd, Dy, Er) complexes.

A series of phosphonate ester supported lanthanide complexes bearing functionalities for subsequent immobilisation on semiconductor surfaces are prepared. Six phosphonate ester ligands (L1-L6) with varying aromatic residues are synthesised. Subsequent complexation with lanthanide chloride or -nitrate precursors (Ln = La, Nd, Dy, Er) affords the corresponding mono- or dimeric lanthanide model complexes [LnX3(L1-L3 or L5-L6)3]n (X = NO3, Cl; n = 1 (Nd, Dy, Er), 2 (La, Nd)) or [LnCl2Br(L4-Br)2(L4-Cl)]n (n = 1 (Nd, Dy, Er), 2 (La, Nd)) (1-32).

HDL-C, ApoA1 and VLDL-TG as biomarkers for the carotid plaque presence in patients with metabolic syndrome.

Aim: Hypercholesterolemia and hyper LDL-C are associated with the atherosclerosis (AS). The current study was performed to evaluate the implication of the others lipoproteins (HDL, LDL, VLDL) and apolipoproteins (ApoA1, ApoB100) with subclinical atherosclerosis (carotid plaque) in patients with metabolic syndrome (MetS) free from cardiovascular disease (CVD).

Methods: Prospective transversal study was conducted in patients with MetS free from cardiovascular disease (CVD).

Single-photon emission from single InGaAs/GaAs quantum dots grown by droplet epitaxy at high substrate temperature.

The authors report single-photon emission from InGaAs quantum dots grown by droplet epitaxy on (100) GaAs substrates using a solid-source molecular beam epitaxy system at elevated substrate temperatures above 400°C without post-growth annealing. High-resolution micro-photoluminescence spectroscopy exhibits sharp excitonic emissions with lifetimes ranging from 0.7 to 1.

Enhancing the optical excitation efficiency of a single self-assembled quantum dot with a plasmonic nanoantenna.

We demonstrate how the controlled positioning of a plasmonic nanoparticle modifies the photoluminescence of a single epitaxial GaAs quantum dot. The antenna particle leads to an increase of the luminescence intensity by about a factor of 8. Spectrally and temporally resolved photoluminescence measurements prove an increase of the quantum dot’s excitation rate.

Epitaxial quantum dots in stretchable optical microcavities.

Arrays of GaAs microring optical resonators with embedded InGaAs quantum dots (QDs) are placed on top of Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) piezoelectric actuators, which allow the microcavities to be reversibly "stretched" or "squeezed" by applying relatively large biaxial stresses at low temperatures. The emission energy of both QDs and optical modes red- or blue- shift depending on the strain sign, with the QD emission shifting more rapidly than the optical mode with applied strain. The QD energy shifts are used to estimate the strain in the structures based on linear deformation potential theory and the finite element method.

Electrospray ion beam deposition: soft-landing and fragmentation of functional molecules at solid surfaces.

The ion beam deposition (IBD) of rhodamine dye molecules on solid surfaces in high vacuum is explored in order to characterize the possibility of fabricating molecular coatings or nanostructures from nonvolatile molecules. Molecular ion beams with a well-defined composition are deposited on silicon oxide surfaces with a controlled kinetic energy. Photoluminescence spectroscopy and time-of-flight secondary ion mass spectrometry (TOF-SIMS) are employed in order to characterize the sample with respect to coverage, homogeneity, and the fraction of intact landed ions (soft-landing ratio).

Self-Assembled Quantum Dot Molecules.

Semiconductor quantum dot molecules (QDMs) are systems composed of two or more closely spaced and interacting QDs. QDMs are receiving much attention both as playground for studying coupling and energy transfer processes between "artificial atoms" and as new systems, which substantially extend the range of possible applications of QDs. QDMs can be conveniently fabricated by self-assembly either through chemical synthesis or epitaxial growth.

Wavelength tunable triggered single-photon source from a single CdTe quantum dot on silicon substrate.

Triggered single-photon emission from a single CdTe quantum dot (QD) grown on Si(001) substrate is demonstrated for the first time. The emission wavelength of QDs can be tuned in a wide spectral range (more than 8 meV) using a focused laser beam. A nearly perfect single-photon emission from the exciton lines is preserved even after energy tuning.

Optical properties of a wrinkled nanomembrane with embedded quantum well.

A wrinkled nanomembrane with embedded quantum well (QW), fabricated by the partial release and bond back of epitaxial layers upon underetching, is investigated by spatially resolved micro-photoluminescence spectroscopy. From the observed QW transition energies and calculations based on the linear deformation potential theory, we find that the bonded back regions are fully relaxed and act on the strain state of the wrinkled QW. Light emission enhancement observed in the wrinkled QW is explained by interference contrast theory.