Sökning: "photoexcited carrier dynamics"

Hittade 3 avhandlingar innehållade orden photoexcited carrier dynamics.

  1. 1. Carrier dynamics in blue and green InGaN LED structures

    Författare :Rinat Yapparov; Saulius Marcinkevičius; Ulrich Theodor Schwarz; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; InGaN quantum wells; interwell transport; near-field scanning optical microscopy; internal quantum efficiency; V-defects; InGaN-kvantbrunnar; transport mellan brunnar; optisk mikroskopi med närafältsskanning; intern kvanteffektivitet; V-defekter; Physics; Fysik; Optics and Photonics; Optik och fotonik;

    Sammanfattning : This thesis focuses on effects that are critical to achieving high internal quantum efficiency (IQE) in GaN-based light-emitting diodes (LEDs) that emit in a broad spectral range, from violet to green-yellow. These effects include interwell carrier transport in multiple quantum well (QW) structures, lateral transport in the QW plane, and radiative and nonradiative recombination. LÄS MER

  3. 2. Optical properties of GaN and InGaN studied by time- and spatially-resolved spectroscopy

    Författare :Tomas Uždavinys; Saulius Marcinkevičius; Audrius Alkauskas; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Gallium nitride; InGaN; near-field microscopy; photoexcited carrier dynamics; intervalley energy; Fe centers; In incorporation; Physics; Fysik;

    Sammanfattning : The past decade has seen rapid expansion in the use of group III-nitride based devices. White InGaN LEDs are substituting incandescent light bulbs, space satellite industry adopting ion-radiation-resistant GaN transistors, and AlGaN deep UV LEDs are increasingly being used for water disinfection and air purification. LÄS MER

  4. 3. Ultrafast Photoinduced Processes in Core and Core–Shell Quantum Dots for Solar Cell Applications “Tiny Crystals for Big Applications”

    Författare :Mohamed Qenawy; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum dots; core–shell; electron injection; hole injection; hole trapping; exciton migration; solar cells; ultrafast dynamics; time-resolved spectroscopy.;

    Sammanfattning : The balance between our demands of energy and the energy we are consuming is not in equilibrium anymore. Therefore, the search for other energy resources is indispensable. Sustainable energy sources offer the alternative to the fossil fuels. LÄS MER