Search for dissertations about: "atomic physics thesis"

Showing result 11 - 15 of 655 swedish dissertations containing the words atomic physics thesis.

  2. 11. Effect of Substrate on Bottom-Up Fabrication and Electronic Properties of Graphene Nanoribbons

    Author : Konstantin Simonov; Olof Karis; Nils Mårtensson; Alexei Preobrajenski; Alessandro Baraldi; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; graphene nanoribbons; bottom-up; substrate; metal contact; electronic structure; electron doping; PES; ARPES; NEXAFS; STM; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : Taking into account the technological demand for the controlled preparation of atomically precise graphene nanoribbons (GNRs) with well-defined properties, the present thesis is focused on the investigation of the role of the underlying metal substrate in the process of building GNRs using bottom-up strategy and on the changes in the electronic structure of GNRs induced by the GNR-metal interaction. The combination of surface sensitive synchrotron-radiation-based spectroscopic techniques and scanning tunneling microscopy with in situ sample preparation allowed to trace evolution of the structural and electronic properties of the investigated systems. READ MORE

  4. 12. Extreme Electron Beams and Brilliant X-rays : Generation, Manipulation and Characterization of Relativistic Electron Beams for and from Plasma-Based Accelerators

    Author : Jonas Björklund Svensson; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; laser; plasma; wakefield; acceleration; accelerator; relativistic; electrons; x-rays; ultra-fast; betatron; laser-wakefield acceleration; plasma-wakefield acceleration; Fysicumarkivet A:2020:Björklund;

    Abstract : This thesis is based on work done by the author on the development of plasma-based electron accelerators driven by ultra-intense laser pulses and dense electron bunches. Plasma based accelerators have several benefits, such as accelerating fields around 1000 times stronger than in “conventional” radio-frequency accelerators, which can allow for shrinking the overall footprint of the accelerator. READ MORE

  5. 13. Precision Improvements of Penning Trap Mass Measurements Using Highly Charged Ions : Applications to solving current problems in fundamental physics

    Author : Tomas Fritioff; Reinhold Schuch; Jürgen Kluge; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Atomic and molecular physics; Atom- och molekylfysik; Physics; fysik;

    Abstract : In my thesis I describe the improvements of the Penning trap mass spectrometer SMILETRAP. The objective of these improvements have been to increase the reliability and the accuracy with which an atomic mass can be measured using highly charged ions. READ MORE

  6. 14. Development of laser spectroscopy for scattering media applications

    Author : Mats Andersson; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Laserteknik; Laser technology; Atom- och molekylärfysik; Atomic and molecular physics; Fysik; Physics; coherent sampling; optical sensor; light absorption; noninvasive measurement; diode laser; scattering of light; laser spectroscopy; fluorescence spectroscopy; remote sensing; Lidar; DIAL;

    Abstract : Laser spectroscopy for both large and small spatial scales has been developed and used in various applications ranging from remote monitoring of atmospheric mercury in Spain to investigation of oxygen contents in wood, human sinuses, fruit, and pharmaceutical solids. Historically, the lidar group in Lund has performed many differential absorption lidar (DIAL) measurements with a mobile lidar system that was first described in 1987. READ MORE

  7. 15. Optical Analysis of biological media - continuous wave diffuse spectroscopy

    Author : Jan Sørensen Dam; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; spatially resolved diffuse reflectance; in vitro diffuse spectroscopy; continuous wave techniques; Nuclear physics; multivariate data analysis.; Kärnfysik; Fysik; Physics; Medicin människa och djur ; Medicine human and vertebrates ; Monte Carlo simulations; light propagation models; multiple scattering; Tissue optics; tissue optical properties; Fysicumarkivet A:2000:Sörensen Dam;

    Abstract : The main topic of this thesis is real-time quantification of relevant chromophores and light scattering elements in biological media. The presented methods and instrumentation are based on continuous wave (steady-state) optical measurements of (a) spatially-resolved diffuse reflectance from bulk media and (b) combined spatially-resolved and goniometric measurements of re-emitted light from thin samples. READ MORE