Sökning: "Direct excitation"
Visar resultat 1 - 5 av 90 avhandlingar innehållade orden Direct excitation.
1. Studies of Light Emitting Devices Based on Er-doped Si and SiGe Layered Structures
Sammanfattning : Doping with rare earth element erbium (Er) in Si has recently attracted a lot of research interest due to potential applications in Si-based opto-electronics. By using molecular beam epitaxy (MBE), precipitate-free Er-doping in Si has been made together with other co-dopants, e.g., oxygen (0) and fluorine (F), up to a level ∼1020 cm-3. LÄS MER
2. Dynamics of Excitation Transfer and Charge Separation in Polymeric Semiconductors
Sammanfattning : Dynamics of optically excited electronic states have been studied in solid films and solutions of semiconducting polymers and model compounds. Transient absorption, monitored in the spectral range from 0.9 eV to 2.5 eV with a time resolution of about 100 fs, was the main experimental technique. LÄS MER
3. Studies of periodic excitation of a turbulent separation bubble
Sammanfattning : .... LÄS MER
4. On Experimental and Theoretical Studies of Dynamics and Particle Production in p+Nucleus and Heavy Ion Reactions
Sammanfattning : Several experiments and theoretical models of intermediate energy heavy ion collision physics are presented in this thesis. Statistical and dynamical aspects of nuclear collisions are widely discussed these days, particularly in connection with the multifragmentation phenomenon and the possible link to a liquid-gas phase transition in the spinodal region of nuclear matter phase diagram. LÄS MER
5. Calcium channel activity and force regulation in smooth muscle: Effects of polyamines and growth stimulation
Sammanfattning : The initial signal for contraction in smooth muscle is an increase in [Ca2+]i. Ca2+ ions can either enter the cytosol from the extracellular medium or be released from intracellular stores. Voltage-operated Ca2+ channels (VOC) play a dominant role in the activation of smooth muscle contraction. LÄS MER