Overcoming power broadening of the quantum dot emission in a pure wurtzite nanowire

Abstract

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Observation of strongly entangled photon pairs from a nanowire quantum dot

“…This technique has been demonstrated to yield defect-free, pure wurtzite nanowires, which is essential to obtain long single-photon coherence27. Figure 1a shows a scanning electron microscopy (SEM) image of a tapered InP nanowire waveguide containing an InAsP segment, 200 nm from the nanowire base, defining the optically active quantum dot that we study.…”

Excitonic structure and pumping power dependent emission blue-shift of type-II quantum dots

“…The meaning of c e and c h in our calculations is that of an average occupation of charge traps55 in QD and CL, respectively, changing from less than one to two electron-hole pairs per QD volume as P is increased. In our understanding, there is probably an important contribution of trap-state filling effect to the emission blue-shift with pumping in type-II.…”

Mesa-top quantum dot single photon emitter arrays: Growth, optical characteristics, and the simulated optical response of integrated dielectric nanoantenna-waveguide systems

“…The resulting interacting SQD -multifunctional LMUs in turn provide the hierarchical building blocks that can be readily interconnected in architectures designed to provide circuit-and system-level functionality. To date, approaches to integrated SQD-LMU structures have been based on either micropillar 7-10 / nanowire [11][12][13][14] or 2D photonic crystal 1,[15][16][17][18][19][20] platforms, the former inherently well-suited to architectures exploiting vertical emission of photons while the latter to horizontal emission. Great progress has been achieved using vertical micropillar / nanowire architecture in realizing single photon emission rate enhancement [7][8][9][10] , purity 8,10,11,13,14 , indistinguishability 9,10,14 and photon collection efficiency control [9][10][11][12][13][14] , all important figures of merit for SPSs.…”

“…The large spectral non-uniformity makes it difficult to spectrally match QD with the light manipulating elements within the tuning range of the well-established spectral tuning technique 19,21 . Another class of SPS is based on QDs in nanowire [12][13][14][48][49][50] structures typically grown via the metal nanoparticle seeded vapor-liquid-solid (VLS) growth mechanism. The nanowire diameter is controlled by the seed particle diameter and in turn the QD lateral size is controlled by the nanowire diameter 48,49 .…”