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Assali, S. (author), Lähnemann, J. (author), Vu, TTT (author), Jöns, K.D. (author), Gagliano, L (author), Verheijen, M. A. (author), Akopian, N. (author), Bakkers, E.P.A.M. (author), Haverkort, J. E.M. (author)
One of the major challenges in the growth of quantum well and quantum dot heterostructures is the realization of atomically sharp interfaces. Nanowires provide a new opportunity to engineer the band structure as they facilitate the controlled switching of the crystal structure between the zinc-blende (ZB) and wurtzite (WZ) phases. Such a...
journal article 2017
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Brenes, Roberto (author), Guo, D. (author), Osherov, Anna (author), Noel, Nakita K. (author), Eames, Christopher (author), Hutter, E.M. (author), Pathak, Sandeep K. (author), Niroui, Farnaz (author), Friend, Richard H. (author), Islam, M. Saiful (author), Snaith, Henry J. (author), Bulović, Vladimir (author), Savenije, T.J. (author), Stranks, Samuel D. (author)
Metal halide perovskites are generating enormous excitement for use in solar cells and light-emission applications, but devices still show substantial non-radiative losses. Here, we show that by combining light and atmospheric treatments, we can increase the internal luminescence quantum efficiencies of polycrystalline perovskite films from 1...
journal article 2017
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Greil, J. (author), Assali, S. (author), Isono, Y. (author), Belabbes, A. (author), Bechstedt, F. (author), Valega MacKenzie, F. O. (author), Yu Silov, A (author), Bakkers, E.P.A.M. (author), Haverkort, J.E.M. (author)
Wurtzite gallium phosphide (WZ GaP) has been predicted to exhibit a direct bandgap in the green spectral range. Optical transitions, however, are only weakly allowed by the symmetry of the bands. While efficient luminescence has been experimentally shown, the nature of the transitions is not yet clear. Here we apply tensile strain up to 6%...
journal article 2016
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Ten Kate, O.M. (author), De Jong, M. (author), Hintzen, H.T. (author), Van der Kolk, E. (author)
Solar cells of which the efficiency is not limited by the Shockley-Queisser limit can be obtained by integrating a luminescent spectral conversion layer into the cell structure. We have calculated the maximum efficiency of state-of-the-art c-Si, pc-Si, a-Si, CdTe, GaAs, CIS, CIGS, CGS, GaSb, and Ge solar cells with and without an integrated...
journal article 2013
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Dogan, I. (author), Kramer, N.J. (author), Westermann, R.H.J. (author), Dohnalova, K. (author), Smets, A.H.M. (author), Verheijen, M.A. (author), Greogorkiewicz, T. (author), Van de Sanden, M.C.M. (author)
We demonstrate a method for synthesizing free standing silicon nanocrystals in an argon/silane gas mixture by using a remote expanding thermal plasma. Transmission electron microscopy and Raman spectroscopy measurements reveal that the distribution has a bimodal shape consisting of two distinct groups of small and large silicon nanocrystals with...
journal article 2013
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Bugarini, G. (author), Reimer, M.E. (author), Zwiller, V. (author)
We report on the optical properties of single quantum dots in nanowires probed along orthogonal directions. We address the same quantum dot from either the nanowire side or along the nanowire axis via reflection on a micro-prism. The collected photoluminescence intensity from nanowires lying on a substrate is improved 3-fold using the prism as...
journal article 2012
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Louwers, D.J. (author), Takizawa, T. (author), Hidaka, C. (author), Van der Kolk, E. (author)
A Eu2+ concentration and temperature dependent energy transfer study from the host lattice to Eu2+ luminescence centers in Ca(1–x)EuxGa2S4 (x = 0.001 to 0.05) was performed with a special streak camera that combines the high timing resolution of a conventional synchroscan operation (<2 ps) with the ability to study long lived states (10?ns???1...
journal article 2012
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Bulgarini, G. (author), Reimer, M.E. (author), Zehender, T. (author), Hocevar, M. (author), Bakkers, E.P.A.M. (author), Kouwenhoven, L.P. (author), Zwiller, V. (author)
Nanowire waveguides with controlled shape are promising for engineering the collection efficiency of quantum light sources. We investigate the exciton lifetime in individual InAsP quantum dots, perfectly positioned on-axis of InP nanowire waveguides. We demonstrate control over the quantum dot spontaneous emission by varying the nanowire...
journal article 2012
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Botterman, J. (author), Van den Eeckhout, K. (author), Bos, A.J.J. (author), Dorenbos, P. (author), Smet, P.F. (author)
In this work we study the persistent luminescence properties of europium-doped alkaline earth silicon oxynitrides (CaSi2O2N2, SrSi2O2N2 and BaSi2O2N2). All compounds show afterglow emission, with an emission spectrum which is similar to the steady state photoluminescence. The afterglow decay time for BaSi2O2N2:Eu and SrSi2O2N2:Eu is about 50 and...
journal article 2012
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Wang, J. (author), Plissard, S. (author), Hocevar, M. (author), Vu, T.T.T. (author), Zehender, T. (author), Immink, G.G.W. (author), Verheijen, M.A. (author), Haverkort, J. (author), Bakkers, E.P.A.M. (author)
We investigate the growth of vertically standing [100] zincblende InP nanowire (NW) arrays on InP (100) substrates in the vapor-liquid-solid growth mode using low-pressure metal-organic vapor-phase epitaxy. Precise positioning of these NWs is demonstrated by electron beam lithography. The vertical NW yield can be controlled by different...
journal article 2012
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Ding, X. (author), Liang, H. (author), Hou, D. (author), Su, Q. (author), Dorenbos, P. (author), Sun, S. (author), Tao, Y. (author)
Ce3+-doped Ba3MgSi2O8 phosphors were prepared by a solid-state reaction route. The photoluminescence properties in the vacuum ultraviolet-vis spectral range and the x ray excited radioluminescence were investigated. Ce3+ ions were found to enter three different sites in the host lattice. Five excitation bands and two emission bands of Ce(1)3+...
journal article 2011
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De Boer, W.D.A.M. (author), Trinh, M.T. (author), Timmerman, D. (author), Schins, J.M. (author), Siebbeles, L.D.A. (author), Greogorkiewicz, T. (author)
We report on investigations of optical generation of carriers in Si nanocrystals embedded in SiO2 matrix by time-resolved induced absorption technique. Results obtained for excitation below and above twice the bandgap energy h???2Eg show very similar decay characteristics (within ?resolution ? 100 fs). When intensity of the signal...
journal article 2011
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Reimer, M.E. (author), van Kouwen, M.P. (author), Barkelid, M. (author)
We report recent progress toward on-chip single photon emission and detection in the near infrared utilizing semiconductor nanowires. Our single photon emitter is based on a single InAsP quantum dot embedded in a p-n junction defined along the growth axis of an InP nanowire. Under forward bias, light is emitted from the single quantum dot by...
journal article 2011
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Van de Krol, R. (author), Ségalini, J. (author), Enache, C.S. (author)
The properties of thin film InVO4 photoanodes for water splitting have been studied. Compact films of InVO4 were prepared by spray pyrolysis and are found to be stable between pH 3 and 11. Although the indirect bandgap is 3.2 eV, a modest amount of visible light absorption is observed. The origin of this absorption is attributed to the presence...
journal article 2011
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Dorenbos, S.N. (author), Sasakura, H. (author), Van Kouwen, M.P. (author), Akopian, N. (author), Adachi, S. (author), Namekata, N. (author), Jo, M. (author), Motohisa, J. (author), Kobayashi, Y. (author), Tomioka, K. (author), Fukui, T. (author), Inoue, S. (author), Kumano, H. (author), Natarajan, C.M. (author), Hadfield, R.H. (author), Zijlstra, T. (author), Klapwijk, T.M. (author), Zwiller, V. (author), Suemune, I. (author)
We report the experimental demonstration of single-photon and cascaded photon pair emission in the infrared, originating from a single InAsP quantum dot embedded in a standing InP nanowire. A regular array of nanowires is fabricated by epitaxial growth on an electron-beam patterned substrate. Photoluminescence spectra taken on single quantum...
journal article 2010
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Akopian, N. (author), Perinetti, U. (author), Wang, L. (author), Rastelli, A. (author), Schmidt, O.G. (author), Zwiller, V. (author)
We study single GaAs quantum dots with optical transitions that can be brought into resonance with the widely used D2 transitions of rubidium atoms. We achieve resonance by Zeeman or Stark shifting the quantum dot levels. We discuss an energy stabilization scheme based on the absorption of quantum dot photoluminescence in a rubidium vapor. This...
journal article 2010
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Van Weert, M.H.M. (author), Den Heijer, M. (author), Van Kouwen, M.P. (author), Algra, R.E. (author), Bakkers, E.P.A.M. (author), Kouwenhoven, L.P. (author), Zwiller, V. (author)
We report voltage dependent photoluminescence experiments on single indium arsenide phosphide (InAsP) quantum dots embedded in vertical surround-gated indium phosphide (InP) nanowires. We show that by tuning the gate voltage, we can access different quantum dot charge states. We study the anisotropic exchange splitting by polarization analysis,...
journal article 2010
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Van der Sar, T. (author), Heeres, E.C. (author), Dmochowski, G.M. (author), De Lange, G. (author), Robledo, L. (author), Oosterkamp, T.H. (author), Hanson, R. (author)
Precise control over the position of a single quantum object is important for many experiments in quantum science and nanotechnology. We report on a technique for high-accuracy positioning of individual diamond nanocrystals. The positioning is done with a home-built nanomanipulator under real-time scanning electron imaging, yielding an accuracy...
journal article 2009
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Perinetti, U. (author), Akopian, N. (author), Samsonenko, Y.B. (author), Bouravleuv, A.D. (author), Cirlin, G.E. (author), Zwiller, V. (author)
We report on optical studies of single InAs quantum dots grown on vicinal GaAs(001) surfaces. To ensure low quantum dot density and appropriate size, we deposit InAs layers 1.4 or 1.5 ML thick, thinner than the critical thickness for Stranski–Krastanov quantum dot formation. These dots show sharp and bright photoluminescence. Lifetime...
journal article 2009
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Krumpel, A.H. (author), Van der Kolk, E. (author), Zeelenberg, D. (author), Bos, A.J.J. (author), Krämer, K.W. (author), Dorenbos, P. (author)
Photo- and thermoluminescence (TL) spectra of NaLaF4:Ln3+ (Ln = Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm) and NaLaF4:Ce3+, Ln3+ (Ln = Nd,Sm,Ho,Er,Tm) are presented and used together with the empirical Dorenbos model in order to establish the 4f energy level positions of all tri- and divalent lanthanide ions doped in NaLaF4. The information will be...
journal article 2008
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