Search for dissertations about: "tunable microwave devices"

Showing result 1 - 5 of 22 swedish dissertations containing the words tunable microwave devices.

  2. 1. High Temperature Superconducting and Tunable Ferroelectric Microwave Devices

    Author : Erik F. Carlsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; varactors; tunable microwave circuits; conformal mapping; cryogenic probe station; ferroelectrics; high temperature superconductors; microwave circuits; narrow-band filters; phase-shifter;

    Abstract : This thesis addresses some applications of High Temperature Superconductors (HTS) and ferroelectric materials in tunable microwave devices and circuits. The work is divided into three main areas: i) modeling of multilayered structures including ferroelectric layers, ii) realization and characterization of tunable coplanar waveguides (CPW), capacitors and resonators based on ferroelectrics, and iii) an investigation of microstrip HTS K-band filters. READ MORE

  4. 2. Tunable surfaces : using polyoxoniobates and -tantalates as molecular building blocks

    Author : Mark Rambaran; C. André Ohlin; Jean-Francois Boily; Mari-Ann Einarsrud; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : This thesis describes and explains the use of aqueous polyoxometalates (POMs), as molecular building blocks in the fabrication of tunable solid-state materials, such as thin films.  Microwave irradiation in the synthesis of Nb10, Nb6 and Ta6 is a rapid and efficient alternative to conventional hydrothermal methods, while offering equal – if not greater yields – of product. READ MORE

  5. 3. Tunable superconducting resonators, subharmonic oscillations and manipulation of microwaves

    Author : Ida-Maria Svensson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; circuit-QED; tunable superconducting resonators; subharmonic oscillations; parametric oscillations; microwave manipulation; frequency down-conversion; driven nonlinear systems; superconducting resonator; SQUID; tunable resonator;

    Abstract : In this thesis I present different types of manipulations of microwave fields using tunable superconducting resonators. A resonator is made tunable by adding one or more superconducting quantum interference devices, SQUIDs. The SQUID consists of a superconducting loop with two Josephson junctions and acts as a tunable nonlinear inductor. READ MORE

  6. 4. Determining and Optimizing the Current and Magnetic Field Dependence of Spin-Torque and Spin Hall Nano-Oscillators : Toward Next-Generation Nanoelectronic Devices and Systems

    Author : Seyed Amir Hossein Banuazizi; Johan Åkerman; Erik Wahlström; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; nanoelectronics; spintronics; nanomagnetism; ferromagnetic materials; microwave oscillators; magnetization dynamics; spin waves; giant magneto-resistance; spin Hall effect; spin-torque nano-oscillators; spin Hall nano-oscillators; numerical modeling; electrical characterization; microwave characterization; magnetic force microscopy.; Fysik; Physics; Teknisk materialvetenskap; Materials Science and Engineering; Informations- och kommunikationsteknik; Information and Communication Technology; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Spin-torque and spin Hall nano-oscillators are nanoscale devices (about 100 nm) capable of producing tunable broadband high-frequency microwave signals ranging from 0.1 GHz to over 65 GHz that several research groups trying to reach up to 200 - 300 GHz. READ MORE

  7. 5. Ferroelectric Thin Films on Si-substrate for Tunable Microwave Applications

    Author : Saeed Abadei; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phase shifter; BaxSr1-xTiO3; Tunable microwave device; Ferroelectric Varactor; Paraelectric; Filter; Na0.5K0.5NbO3; Integrated ferroelectric device; SrTiO3; Ferroelectric;

    Abstract : The thesis presents the development of microwave tunable devices based onferroelectric thin films. The main tasks in this work are the fabrication, optimization, andintegration of ferroelectric thin film into Si-MMIC. READ MORE