Search for dissertations about: "magnetic and optical properties"

Showing result 1 - 5 of 151 swedish dissertations containing the words magnetic and optical properties.

  2. 1. 3D Magnetic Photonic Crystals : Synthesis and Characterization

    Author : Mei Fang; K.Venkat Rao; Lyubov Belova; Rajeev Ahuja; KTH; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURVETENSKAP; NATURAL SCIENCES; magnetic photonic crystals; photonic band gaps; Fe3O4 nanoparticles; silica; Optical physics; Optisk fysik; Materials science; Teknisk materialvetenskap;

    Abstract : This thesis presents the synthesis methods and the characterizations of magnetic Fe3O4 nanoparticles, silica spheres with Fe3O4 nanoparticles embedded, and three dimensional magnetic photonic crystals (MPCs) prepared from the spheres. The structure, material composition, magnetic and optical properties, photonic band gaps (PBGs), as well as how these properties depend on the concentration of the magnetic nanoparticles, are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), superconducting quantum interference device (SQUID), Faraday rotation (FR) and optical spectrophotometers. READ MORE

  4. 2. Magnetic Heterostructures : The Effect of Compositional Modulation on Magnetic Properties

    Author : Inna Soroka; Roger Wäppling; Björgvin Hjörvarsson; Rudolf Schäfer; Uppsala universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Materials science; Magnetism; Sputter deposition; Superlattice; Multilayers; Materialvetenskap; Materials science; Teknisk materialvetenskap;

    Abstract : The effect of compositional modulation on structural and magnetic properties of magnetic heterostructures was explored. The systems under focus were ferromagnetic superlattices Fe81Ni19/Co, metal-insulator multilayers Al2O3/Ni81Fe19, nanoparticles and artificial multilayered pillars. READ MORE

  5. 3. Chitin nanofibers, networks and composites : Preparation, structure and mechanical properties

    Author : Ngesa Ezekiel Mushi; Lars Berglund; Qi Zhou; Shinsuke Ifuku; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chitin; chitin materials; membranes; hydrogels; nanocomposites; mechanical properties; bioinspiration; lobster; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Abstract : Chitin is an important reinforcing component in load-bearing structures in many organisms such as insects and crustaceans (i.e. shrimps, lobsters, crabs etc.). READ MORE

  6. 4. Optical Memories and Processing in Time- and Frequency Domain

    Author : Baozhu Luo; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Optical storage; photon echo; spectral hole burning; nonlinear optics; fiber amplifier; logical operation; phase retrieval; polarization holographic recording and retrieval; optical processing; Atomic and molecular physics; Atom- och molekylärfysik; Fysicumarkivet A:1998:Luo;

    Abstract : Spectral hole burning and photon echoes are the techniques for frequency-selective optical memories, which have the potential to increase areal data storage density by a factor 10**7. They also have the capability to perform in-memory data processing. READ MORE

  7. 5. Formation and Dynamics of Molecular Excitons and their Fingerprints in Nonlinear Optical Spectroscopy

    Author : Pär Kjellberg; Kemisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; supraledare; magnetisk resonans; spektroskopi; Physical chemistry; Fysikalisk kemi; Photochemistry; Fotokemi; Kondenserade materiens egenskaper:elektronstruktur; magnetiska och optiska ; egenskaper elektriska; supraconductors; magnetic resonance; relaxation; spectroscopy; Fysik; Chemistry; Kemi; Condensed matter:electronic structure; electrical; Physics; Redfield relaxation theory ; Inhomogeneous broadening ; Time-dependent density functional theory ; Conjugated polymers ; Three-pulse photon echo ; Molecular excitons ; magnetic and optical properties; Nonlinear spectroscopy ;

    Abstract : An efficient transfer of energy in molecular systems has proven to be of fundamental importance both in nature and industrial applications. The ability of molecules to work together forming collective excitations, so-called excitons, plays a key role in for example the extraordinary fast energy transfer involved in the first steps of photosynthesis. READ MORE