Sökning: "hot carrier"

Visar resultat 1 - 5 av 40 avhandlingar innehållade orden hot carrier.

  1. 1. Hot-carrier extraction in nanowires

    Författare :Jonatan Fast; NanoLund: Center for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Nanowire; Hot carrier; photovoltaic; Thermoelectric; Fysicumarkivet A:2023:Fast;

    Sammanfattning : A hot-carrier solar cell aims to generate power from energetic, photoexcited, charge carriers, so called hot carriers, in order to reach higher conversion efficiencies than current solar cell technology.Creating a hot-carrier solar cell has proven challenging for two main reasons: hot carriers lose their energy very quickly, and they need to be extracted over distances of a few hundrednanometers via energy selective filters. LÄS MER

  2. 2. Charge Separation on Localized Surface Plasmon and Hot Carrier Transfer to Semiconductors

    Författare :Yocefu Hattori; Jacinto Sá; Stephan Link; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Plasmonics; hot carrier; metal nanoparticles; semiconductors; ultrafast transient absorption spectroscopy; Chemistry with specialization in Physical Chemistry; Kemi med inriktning mot fysikalisk kemi;

    Sammanfattning : The relatively recent discovery that plasmonic nanoparticles generate energetic electron-hole pairs known as hot carriers has been the source of interest from many scientific groups. The capability to extract these short-lived hot carriers from metal nanoparticles (NPs) might potentially lead to applications in solar cells, photodetection, and photocatalysis. LÄS MER

  3. 3. Graphene Hot-electron Transistors

    Författare :Sam Vaziri; Mikael Östling; Max Lemme; Suman Datta; KTH; []
    Nyckelord :Graphene; hot-electron transistors; graphene base transistors; GBT; cross-plane carrier transport; tunneling; ballistic transport; heterojunction transistors; graphene integration; graphene transfer; Informations- och kommunikationsteknik; Information and Communication Technology;

    Sammanfattning : Graphene base transistors (GBTs) have been, recently, proposed to overcome the intrinsic limitations of the graphene field effect transistors (GFETs) and exploit the graphene unique properties in high frequency (HF) applications. These devices utilize single layer graphene as the base material in the vertical hot-electron transistors. LÄS MER

  4. 4. Time-Resolved Photoemission Electron Microscopy: Development and Applications

    Författare :Lukas Wittenbecher; NanoLund: Center for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PEEM; time-resolved PEEM; ultrafast optics; pulse shaping; plasmonics; semiconductor nanowires; hot electrons; ultrafast microscopy; charge carrier relaxation;

    Sammanfattning : Time-resolved photoemission electron microscopy (TR-PEEM) belongs to a class of experimental techniquescombining the spatial resolution of electron-based microscopy with the time resolution of ultrafast opticalspectroscopy. This combination provides insight into fundamental processes on the nanometer spatial andfemto/picosecond time scale, such as charge carrier transport in semiconductors or collective excitations ofconduction band electrons at metal surfaces. LÄS MER

  5. 5. District Heating for Residential Areas with Single-Family Housing -with Special Emphasis on Domestic Hot Water Comfort

    Författare :Tommy Persson; Energihushållning; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; low heat density; District heating; single-family housing; domestic hot water comfort; domestic hot water control; heat losses; supply temperature; thermostatic valves; Energiforskning; Energy research; marketing strategies; market penetration;

    Sammanfattning : The concept of district heating (DH) involves centralised heat production where heat is distributed to consumers via a piping network. It is essential that benefits achieved from concentrated, large-scale production instead of local production in each building exceed the costs associated with heat distribution. LÄS MER