Listar por tema "Quantum dots"

Mostrando ítems 1-20 de 25

    • openAccess   Charge control in laterally coupled double quantum dots 

      Muñoz Matutano, G.; Royo Valls, Miguel; Climente, Juan I.; Canet Ferrer, J.; Fuster, D.; Alonso-Jordá, Pedro; Fernández Martínez, Iván; Martínez-Pastor, Juan P.; González Diez, Yolanda; González Sotos, Luisa; Briones, Fernando; Alen Millán, B. American Physical Society (2011-07-27)
      We investigate the electronic and optical properties of InAs double quantum dots grown on GaAs (001) and laterally aligned along the [110] crystal direction. The emission spectrum has been investigated as a function of a ...

    • openAccess   Colloidal PbS and PbSeS Quantum Dot Sensitized Solar Cells Prepared by Electrophoretic Deposition 

      Parsi Benehkohal, Nima; González Pedro, Victoria; Boix, Pablo P; Chavhan, Sudam; Tena-Zaera, Ramón; Demopoulos, George P.; Mora-Sero, Ivan American Chemical Society (2012)
      Here we report the developement of quantum dot sensitized solar cells (QDSCs) using colloidal PbS and PbSeS QDs and polysulfide electrolyte for high photocurrents. QDSCs have been prepared in a novel sensitizing way employing ...

    • openAccess   Coupled donors in quantum dots: quantum size and dielectric mismatch effects 

      Movilla, Jose L.; Ballester Caudet, Ana; Planelles, Josep American Physical Society (2009)
      Spatial and dielectric confinement modulations of the spontaneous emission rates, transition energies, and charge-density distributions of a singly ionized double donor system (D2+) in a spherical quantum dot are calculated ...

    • openAccess   Development of perovskite optoelectronic devices on flexible substrates 

      Hassanabadi, Ehsan Universitat Jaume I (2022-03-08)
      In this thesis, first, the monolithic integration of a perovskite-based optical waveguide amplifier together with a photodetector on a nanocellulose substrate is shown to demonstrate the feasibility of a stretchable signal ...

    • openAccess   Dielectric confinement in quantum dots of arbitrary shape within the local spin density approximation: Diluted regimes in elongated quantum dots 

      Movilla, Jose L.; Pi, Martí; Planelles, Josep American Institute of Physics (2010)
      We propose a simplified and computationally feasible model accounting for the dielectric confinement in arbitrarily shaped many-electron quantum dots, within the local spin density approximation. The model yields quite ...

    • openAccess   Dielectric control of spin in semiconductor spherical quantum dots 

      Royo Valls, Miguel; Rajadell Viciano, Fernando; Planelles, Josep American Institute of Physics (2008)
      The ground state electronic configuration of semiconductor spherical quantum dots populated with different numbers of excess electrons, for different radii and dielectric constants of the embedding medium is calculated ...

    • openAccess   Dominant channels of exciton spin relaxation in photoexcited self-assembled (In,Ga)As quantum dots 

      Liao, Yu-Huai; Climente, Juan I.; Cheng, Shun-Jen American Physical Society (2011-04-22)
      We present a comprehensive theoretical investigation of spin relaxation processes of excitons in photoexcited self-assembled quantum dots. The exciton spin relaxations are considered between dark- and bright-exciton states ...

    • openAccess   Effect of nanostructured electrode architecture and semiconductor deposition strategy on the photovoltaic performance of quantum dot sensitized solar cells 

      Samadpour, Mahmoud; Gimenez, Sixto; Pérez Boix, Pablo; Shen, Qing; Calvo, Mauricio E.; Taghavinia, Nima; Iraji Zad, Azam; toyoda, taro; Míguez, Hernán; Mora-Sero, Ivan Elsevier (2012)
      Here we analyze the effect of two relevant aspects related to cell preparation on quantum dot sensitized solar cells (QDSCs) performance: the architecture of the TiO2 nanostructured electrode and the growth method of quantum ...

    • openAccess   Effect of organic and inorganic passivation in quantum-dot-sensitized solar cells 

      De La Fuente, M. S.; S. Sánchez, Rafael; González Pedro, Victoria; Boix, Pablo P; Mhaisalkar, S. G.; Rincón, Marina; Bisquert, Juan; Mora-Sero, Ivan American Chemical Society (2013)
      The effect of semiconductor passivation on quantum-dot-sensitized solar cells (QDSCs) has been systematically characterized for CdS and CdS/ZnS. We have found that passivation strongly depends on the passivation agent, ...

    • openAccess   Electrons, holes, and excitons in GaAs polytype quantum dots 

      Climente, Juan I.; Segarra, Carlos; Rajadell Viciano, Fernando; Planelles, Josep American Institute of Physics (2016)
      Single and multi-band k⋅p Hamiltonians for GaAs crystal phase quantum dots are used to assess ongoing experimental activity on the role of such factors as quantum confinement, spontaneous polarization,valence band mixing, ...

    • openAccess   Emission spectrum of quasiresonant laterally coupled quantum dots 

      Royo Valls, Miguel; Climente, Juan I.; Planelles, Josep American Physical Society (2011-12-21)
      We calculate the emission spectrum of neutral and charged excitons in a pair of laterally coupled InGaAs quantum dots with nearly degenerate energy levels. As the interdot distance decreases, a number of changes take place ...

    • openAccess   Exciton storage in type-ll quantum dots using the optical Aharonov-Bohm effect 

      Climente, Juan I.; Planelles, Josep AIP Publishing (2014-05-12)
      We investigate the bright-to-dark exciton conversion efficiency in type-II quantum dots subject to a perpendicular magnetic field. To this end, we take the exciton storage protocol recently proposed by Simonin and ...

    • openAccess   From quantum dots to quantum wires: electronic structure of semiconductor nanorods 

      Planelles, Josep; Royo Valls, Miguel; Ballester Caudet, Ana; Pi, Martí American Physical Society (2009)
      The transition bridge between zero-dimensional quantum dots and one-dimensional quantum wires is explored theoretically by means of the construction of the addition energy spectra of nanorods with different lengths. Spin ...

    • openAccess   Harnessing infrared photons for photoelectrochemical hydrogen generation. A PbS quantum dot based "quasi-artificial leaf" 

      Trevisan, Roberto; Rodenas, Pau; González Pedro, Victoria; Sima, Cornelia; S. Sánchez, Rafael; Barea, Eva M; Mora-Sero, Ivan; Fabregat-Santiago, Francisco; Gimenez, Sixto American Chemical Society (2013)
      Hydrogen generation by using quantum dot (QD) based heterostructures has emerged as a promising strategy to develop artificial photosynthesis devices. In the present study, we sensitize mesoporous TiO2 electrodes with ...

    • openAccess   Hole spin mixing in InAs Quantum Dot Molecules 

      Doty, Matthew F.; Climente, Juan I.; Greilich, A.; Yakes, Michael; Bracker, Allan S.; Gammon, Daniel American Physical Society (2010)
      The spin state of holes confined in single InAs quantum dots have recently emerged as a promising system for the storage or manipulation of quantum information. These holes are often assumed to have no mixing between ...

    • openAccess   Large hole spin anticrossings in InAs/GaAs double quantum dots 

      Rajadell Viciano, Fernando; Planelles, Josep; Climente, Juan I. AIP Publishing (2013-09-23)
      We show that hole states in InAs/GaAs double quantum dots can exhibit spin anticrossings of up to 1 meV, according to simulations with a three dimensional Burt-Foreman Hamiltonian including strain and piezoelectric fields. ...

    • closedAccess   Large improvement of electron extraction from CdSe quantum dots into a TiO<sub>2</sub> thin layer by N3 dye coabsorption 

      Mora-Sero, Ivan; Dittrich, Thomas; Susha, A. S.; Rogach, A. L.; Bisquert, Juan Elsevier (2008)
      Extraction of electrons and holes photogenerated in CdSe quantum dots (QD) of 2.3 nm diameter, is monitored by Surface Photovoltage Spectroscopy. The extraction of electrons into a thin TiO<sub>2</sub> layer increases ...

    • openAccess   Mixed correlation phases in elongated quantum dots 

      Ballester Caudet, Ana; Escartín, J. M.; Movilla, Jose L.; Pi, Martí; Planelles, Josep American Physical Society (2010-09-07)
      It is theoretically shown, within the local spin-density-functional theory framework, that inhomogeneous confining potentials in elongated, diluted N-electron quantum dots may lead to the formation of mixed phases in which ...

    • openAccess   Perovskite-Quantum Dots Interface: Deciphering its Ultrafast Charge Carrier Dynamics 

      Galar, Pavel; Piatkowski, Piotr; Ngo, Thi Tuyen; Gutiérrez Tovar, Mario; Mora-Sero, Ivan; Douhal, Abderrazzak Elsevier (2018)
      Understanding electron and hole (e,h) transport at semiconductor interfaces is paramount to developing efficientoptoelectronic devices. Halide perovskite/semiconductor quantum dots (QDs) have emerged as smart hybridsystems ...

    • closedAccess   Quantum dot–polymethacrylate composites for the analysis of NOx by fluorescence spectroscopy 

      Fabregat Tena, Víctor; Izquierdo Arcusa, María Ángeles; Burguete, M. Isabel; Galindo, Francisco; Luis, Santiago V. Elsevier (2012)
      A new type of hybrid materials composed by core–shell (CdSe/ZnS) quantum dots adsorbed on polymethacrylate surfaces has been synthesized and characterized, specially by means of time-resolved fluorimetry. The ability of ...