Sökning: "K Kim"

Visar resultat 1 - 5 av 12 avhandlingar innehållade orden K Kim.

  1. 1. Novel tantalate-niobate films for microwaves

    Författare :Jang-Yong Kim; Alex Grishin; Andrey B. Kozyrev; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ferroelectrics; sodium potassium niobates; silver tantalate niobate; barium stronitium titanate; Electronics; Elektronik;

    Sammanfattning : Microwave materials have been widely used in a variety of applications ranging from communication devices to military satellite services, and the study of materials properties at microwave frequencies and the development of functional microwave materials have always been among the most active areas in solid-state physics, materials science, and electrical and electronic engineering. In recent years, the increasing requirements for the development of high speed, high frequency circuits and systems require complete understanding of the properties of materials function at microwave frequencies. LÄS MER

  2. 2. Micromachined epitaxial colossal mognetoresistors for uncooled infrared bolometer

    Författare :Joo-Hyung Kim; Alexander M. Grishin; Yael Nemirosky; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; La0.67 Sr; Ca 0.33MnO3 LSCMO ; La0.67Sr0.33MnO3 LSMO ; Electrophysics; Elektrofysik;

    Sammanfattning : High quality perovskite manganites, La1-xAxMnO3 (A = Ca, Sr, Ba) are very attractive materials due to their great application potential for magnetic memory, uncooled infrared (IR) microbolometer and spintronics devices. This thesis presents studies of the growth and material characterization (including structural, electrical, magnetic and noise) of epitaxial manganite films on Si and GaAs. LÄS MER

  3. 3. Processing and On-Wafer Test of Ferroelectric Film Microwave Varactors

    Författare :Jang-Yong Kim; Alexander Grishin; Dag Winkler; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; : ferroelectrics; sodium potassium niobates; silver tantalite niobate; barium strontium titanate; thin films; pulsed laser deposition; rf magnetron sputtering; coplanar waveguide; photolithography; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

    Sammanfattning : Microwave materials have been widely used in a variety of applications ranging from communication devices to military satellite services, and the study of materials properties at microwave frequencies and the development of functional microwave materials have always been among the most active areas in solid-state physics, materials science, electrical and electronic engineering. In recent years, the increasing requirements for the development of high speed, high frequency circuits and systems require complete understanding of the properties of materials function at microwave frequencies. LÄS MER

  4. 4. Ab initio Lattice Dynamics : Hydrogen-dense and Other Materials

    Författare :Duck Young Kim; Rajeev Ahuja; Richard Needs; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Density functional theory; Density functional perturbation theory; Hydrogen-dense materials; Phase transition; High pressure; Ab initio lattice dynamics; Superconductivity; Quasi-particle approximation; Physics; Fysik;

    Sammanfattning : This thesis presents a theoretical study of materials under high pressure using ab initio lattice dynamics based on density functional theory and density functional perturbation theory using both super-cell and linear response approach. Ab initio lattice dynamics using super-cell approach is applied to compare our theoretical predictions with experimental findings. LÄS MER

  5. 5. Abelian affine group schemes, plethories, and arithmetic topology

    Författare :Magnus Carlson; Tilman Bauer; Minhyong Kim; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In Paper A we classify plethories over a field of characteristic zero. All plethories over characteristic zero fields are ``linear", in the sense that they are free plethories on a bialgebra. For the proof of this classification we need some facts from the theory of ring schemes where we extend previously known results. LÄS MER