Sökning: "tunable microwave devices"
Visar resultat 1 - 5 av 22 avhandlingar innehållade orden tunable microwave devices.
1. High Temperature Superconducting and Tunable Ferroelectric Microwave Devices
Sammanfattning : 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. LÄS MER
2. Tunable surfaces : using polyoxoniobates and -tantalates as molecular building blocks
Sammanfattning : 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. LÄS MER
3. Tunable superconducting resonators, subharmonic oscillations and manipulation of microwaves
Sammanfattning : 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. LÄS MER
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
Sammanfattning : 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. LÄS MER
5. Ferroelectric Thin Films on Si-substrate for Tunable Microwave Applications
Sammanfattning : 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. LÄS MER