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  1. Artikel: Identification of the Segregation Kinetics of Ultrathin GaAsSb/GaAs Films Using AlAs Markers.

    Gonzalez, David / Flores, Sara / Braza, Verónica / Reyes, Daniel F / Carro, Alejandro Gallego / Stanojević, Lazar / Schwarz, Malte / Ulloa, Jose María / Ben, Teresa

    Nanomaterials (Basel, Switzerland)

    2023  Band 13, Heft 5

    Abstract: For optoelectronic devices from the near to the far infrared, the advantages of using ultrathin III-Sb layers as quantum wells or in superlattices are well known. However, these alloys suffer from severe surface segregation problems, so that the actual ... ...

    Abstract For optoelectronic devices from the near to the far infrared, the advantages of using ultrathin III-Sb layers as quantum wells or in superlattices are well known. However, these alloys suffer from severe surface segregation problems, so that the actual profiles are very different from the nominal ones. Here, by inserting AlAs markers within the structure, state-of-the-art transmission electron microscopy techniques were used to precisely monitor the incorporation/segregation of Sb in ultrathin GaAsSb films (from 1 to 20 monolayers (MLs)). Our rigorous analysis allows us to apply the most successful model for describing the segregation of III-Sb alloys (three-layer kinetic model) in an unprecedented way, limiting the number of parameters to be fitted. The simulation results show that the segregation energy is not constant throughout the growth (which is not considered in any segregation model) but has an exponential decay from 0.18 eV to converge asymptotically towards 0.05 eV. This explains why the Sb profiles follow a sigmoidal growth model curve with an initial lag in Sb incorporation of 5 MLs and would be consistent with a progressive change in surface reconstruction as the floating layer is enriched.
    Sprache Englisch
    Erscheinungsdatum 2023-02-22
    Erscheinungsland Switzerland
    Dokumenttyp Journal Article
    ZDB-ID 2662255-5
    ISSN 2079-4991
    ISSN 2079-4991
    DOI 10.3390/nano13050798
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  2. Artikel: Suppressing the Effect of the Wetting Layer through AlAs Capping in InAs/GaAs QD Structures for Solar Cells Applications.

    Ruiz, Nazaret / Fernández, Daniel / Stanojević, Lazar / Ben, Teresa / Flores, Sara / Braza, Verónica / Carro, Alejandro Gallego / Luna, Esperanza / Ulloa, José María / González, David

    Nanomaterials (Basel, Switzerland)

    2022  Band 12, Heft 8

    Abstract: Recently, thin AlAs capping layers (CLs) on InAs quantum dot solar cells (QDSCs) have been shown to yield better photovoltaic efficiency compared to traditional QDSCs. Although it has been proposed that this improvement is due to the suppression of the ... ...

    Abstract Recently, thin AlAs capping layers (CLs) on InAs quantum dot solar cells (QDSCs) have been shown to yield better photovoltaic efficiency compared to traditional QDSCs. Although it has been proposed that this improvement is due to the suppression of the capture of photogenerated carriers through the wetting layer (WL) states by a de-wetting process, the mechanisms that operate during this process are not clear. In this work, a structural analysis of the WL characteristics in the AlAs/InAs QD system with different CL-thickness has been made by scanning transmission electron microscopy techniques. First, an exponential decline of the amount of InAs in the WL with the CL thickness increase has been found, far from a complete elimination of the WL. Instead, this reduction is linked to a higher shield effect against QD decomposition. Second, there is no compositional separation between the WL and CL, but rather single layer with a variable content of InAlGaAs. Both effects, the high intermixing and WL reduction cause a drastic change in electronic levels, with the CL making up of 1-2 monolayers being the most effective configuration to reduce the radiative-recombination and minimize the potential barriers for carrier transport.
    Sprache Englisch
    Erscheinungsdatum 2022-04-15
    Erscheinungsland Switzerland
    Dokumenttyp Journal Article
    ZDB-ID 2662255-5
    ISSN 2079-4991
    ISSN 2079-4991
    DOI 10.3390/nano12081368
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel: Tailoring of AlAs/InAs/GaAs QDs Nanostructures via Capping Growth Rate.

    Ruiz, Nazaret / Fernandez, Daniel / Luna, Esperanza / Stanojević, Lazar / Ben, Teresa / Flores, Sara / Braza, Verónica / Gallego-Carro, Alejandro / Bárcena-González, Guillermo / Yañez, Andres / Ulloa, José María / González, David

    Nanomaterials (Basel, Switzerland)

    2022  Band 12, Heft 14

    Abstract: The use of thin AlA capping layers (CLs) on InAs quantum dots (QDs) has recently received considerable attention due to improved photovoltaic performance in QD solar cells. However, there is little data on the structural changes that occur during capping ...

    Abstract The use of thin AlA capping layers (CLs) on InAs quantum dots (QDs) has recently received considerable attention due to improved photovoltaic performance in QD solar cells. However, there is little data on the structural changes that occur during capping and their relation to different growth conditions. In this work, we studied the effect of AlA capping growth rate (CGR) on the structural features of InAs QDs in terms of shape, size, density, and average content. As will be shown, there are notable differences in the characteristics of the QDs upon changing CGR. The Al distribution analysis in the CL around the QDs was revealed to be the key. On the one hand, for the lowest CGR, Al has a homogeneous distribution over the entire surface, but there is a large thickening of the CL on the sides of the QD. As a result, the QDs are lower, lenticular in shape, but richer in In. On the other hand, for the higher CGRs, Al accumulates preferentially around the QD but with a more uniform thickness, resulting in taller QDs, which progressively adopt a truncated pyramidal shape. Surprisingly, intermediate CGRs do not improve either of these behaviors, resulting in less enriched QDs.
    Sprache Englisch
    Erscheinungsdatum 2022-07-21
    Erscheinungsland Switzerland
    Dokumenttyp Journal Article
    ZDB-ID 2662255-5
    ISSN 2079-4991
    ISSN 2079-4991
    DOI 10.3390/nano12142504
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Buch: 700 godina medicine u Srba

    Stanojević, Lazar

    700 ans de médecine chez les Serbes. Glavni urednik: Lazar Stanojević

    (Galerija Srpske akademije nauka i umetnosti. [Katalog] 13)

    1971  

    Titelvarianten 700 ans de médecine chez les Serbes
    Serientitel Galerija Srpske akademije nauka i umetnosti. [Katalog] 13
    Mesh-Begriff(e) History of Medicine
    Schlagwörter Yugoslavia
    Sprache Kroatisch
    Umfang 416 p., illus., ports.
    Verlag Srpska akademija nauka i umetnosti
    Erscheinungsort Beograd
    Dokumenttyp Buch
    Anmerkung In Serbo-Croatian and French.
    Datenquelle Katalog der US National Library of Medicine (NLM)

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  5. Buch: Medicinski leksikon

    Kostić, Aleksandar / Stanojević, Lazar

    1970  

    Verfasserangabe [Urednici: Aleksandar Kostić i Lazar Stanojević]
    Schlagwörter Dictionaries, Medical / Serbo-Croatian
    Sprache Kroatisch
    Umfang ix, 784 p.
    Ausgabenhinweis 3. izd.
    Verlag Medicinska knjiga
    Erscheinungsort Beograd
    Dokumenttyp Buch
    Datenquelle Katalog der US National Library of Medicine (NLM)

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  6. Buch: Basic aims and principles of workers training

    Marković, Milorad / Stanojević, Lazar

    (Yugoslav Experiences - Questions Answered ; 6)

    1964  

    Titelübersetzung Osnovni ciljeve i principi obrazovanja radnika
    Körperschaft Confederation of Trade Unions of Yugoslavia
    Verfasserangabe editor: Milorad Marković. Transl. by: Lazar Stanojević. Publ. by: Confederation of Trade Unions of Yugoslavia
    Serientitel Yugoslav Experiences - Questions Answered ; 6
    Schlagwörter Berufsbildung ; Jugoslawien
    Umfang 42 S
    Erscheinungsort Beograd
    Dokumenttyp Buch
    Datenquelle ECONomics Information System

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  7. Buch: Socio-economic scope of Yugoslav trade union action

    Marković, Milorad / Stanojević, Lazar

    (Yugoslav Experiences - Questions Answered ; 1)

    1964  

    Titelübersetzung U kakvim ekonomskim i društvenim uslovima dejstvuju jugoslovenski sindikati
    Körperschaft Confederation of Trade Unions of Yugoslavia
    Verfasserangabe editor: Milorad Marković. Transl. by: Lazar Stanojević. Publ. by: Confederation of Trade Unions of Yugoslavia
    Serientitel Yugoslav Experiences - Questions Answered ; 1
    Schlagwörter Wirtschaftsordnung ; Arbeitergewerkschaft ; Jugoslawien
    Umfang 37 S
    Erscheinungsort Beograd
    Dokumenttyp Buch
    Datenquelle ECONomics Information System

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  8. Buch: O zdravlju i bolesti

    Stanojević, Lazar

    1954  

    Mesh-Begriff(e) Medicine
    Sprache Serbisch
    Umfang 193 p.
    Dokumenttyp Buch
    Anmerkung Contains errata slip.
    Datenquelle Katalog der US National Library of Medicine (NLM)

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  9. Buch: Social insurance and how it functions

    Marković, Milorad / Stanojević, Lazar

    (Yugoslav Experiences - Questions Answered ; 5)

    1964  

    Titelübersetzung Kolika su i kako se ostavaruju prava iz socijalnog osiguranja
    Körperschaft Confederation of Trade Unions of Yougoslavia
    Verfasserangabe editor: Milorad Marković. Transl. by: Lazar Stanojević. Publ. by: Confederation of Trade Unions of Yougoslavia
    Serientitel Yugoslav Experiences - Questions Answered ; 5
    Schlagwörter Sozialversicherung ; Jugoslawien
    Umfang 17 S
    Erscheinungsort Beograd
    Dokumenttyp Buch
    Datenquelle ECONomics Information System

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  10. Buch: Die physiologische und klinische Bedeutung des Blutammoniaks

    Stanojević, Lazar

    1938  

    Schlagwörter Ammonia / Assimilation and excretion ; Blood / Chemistry
    Sprache Deutsch
    Umfang 64 p., ill.
    Verlag Steinkopff
    Erscheinungsort Dresden
    Dokumenttyp Buch
    Datenquelle Katalog der US National Library of Medicine (NLM)

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