Search for dissertations about: "Wei Si"

Showing result 1 - 5 of 8 swedish dissertations containing the words Wei Si.

2. 1. Empirical Essays in Labor and Development Economics

   Author : Wei Si; Andreas Madestam; Peter Fredriksson; Anna Sjögren; Stockholms universitet; []
   Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Peer Effect; Knowledge Spillover; Cognitive Distance; Research Productivity; Public Health Insurance; Labor Supply; Job Mobility; Informality; Labor Market; Higher Education Expansion; Gender Norms; Gender Equality; Economics; nationalekonomi;

   Abstract : This thesis consists of three self-contained empirical essays in labor and development economics.Diverse Expertise, Peer Effects, and Research Productivity: Does diversity in idea space matter? We empirically explore whether the cognitive distance between collaborators affects peer effects and productivity in creating knowledge. READ MORE

4. 2. Growth and Characterization of Strain-engineered Si/SiGe Heterostructures Prepared by Molecular Beam Epitaxy

   Author : Ming Zhao; Wei-Xin Ni; Göran Hansson; Kang L. Wang; Linköpings universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Si SiGe; Strain engineering; Molecular beam epitaxy; THz; Quantum cascade; Strain relaxation; Materials science; Teknisk materialvetenskap;

   Abstract : The strain introduced by lattice mismatch is a built-in characteristic in Si/SiGe heterostructures, which has significant influences on various material properties. Proper design and precise control of strain within Si/SiGe heterostructures, i.e. READ MORE

5. 3. Near-infrared photodetectors based on Si/SiGe nanostructures

   Author : Anders Elfving; Wei-Xin Ni; Thomas P. Pearsall; Linköpings universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; SiGe; Ge dots; nanostructures; molecular beam epitaxy; photodetector; Semiconductor physics; Halvledarfysik;

   Abstract : Two types of photodetectors containing Ge/Si quantum dots have been fabricated based on materials grown by molecular beam epitaxy and characterized with several experimental techniques. The aim was to study new device architectures with the implementation of Ge nanostructures, in order to obtain high detection efficiency in the near infrared range at room temperature. READ MORE

6. 4. Si-based structures for light emission and detection

   Author : Amir Karim; Göran Hansson; Wei-Xin Ni; Tom Gregorkiewicz; Linköpings universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

   Abstract : Efforts to improve the optical performance of the indirect bandgap semiconductor silicon (Si) has been a major subject of research in the field of Si photonics due to the promising applications of Si based light emitters and detectors for optical communication. With that motivation three different Si based material systems were investigated; Si:Er/O layered structures, SiGe quantum dots and SiSn nano structures, all grown using the technique of molecular beam epitaxy (MBE). READ MORE

7. 5. Ferromagnetic Resonance as a Probe of Magnetization Dynamics : A Study of FeCo Thin Films and Trilayers

   Author : Yajun Wei; Peter Svedlindh; Sujeet Chaudhary; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; ferromagnetic resonance FMR ; Gilbert damping; magnetic coupling; FeCo;

   Abstract : The high frequency dynamic magnetic responses of FeCo thin films and structures have been investigated mainly using ferromagnetic resonance (FMR) technique.The FMR resonance condition and linewidth are first derived from the dynamic Landau- Lifshitz-Gilbert equation, followed by a study of the conversion between FMR field and frequency linewidths. READ MORE