Search for dissertations about: "spin wave"

Showing result 1 - 5 of 80 swedish dissertations containing the words spin wave.

2. 1. Linear, Non-Linear, and Synchronizing Spin Wave Modes in Spin Hall Nano-Oscillators

   Author : Hamid Mazraati; Johan Åkerman; Dario Arena; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; spin Hall effect; spin Hall nano-oscillators; threshold current; microwave; spin wave; synchronization; Fysik; Physics;

   Abstract : Spin Hall nano-oscillators (SHNOs) are nanoscale spintronic devices that generate microwave signals with highly tunable frequency. This thesis focuses on improving the signal quality of nanoconstriction-based SHNOs and also on developing a better understanding of their magnetization dynamics. READ MORE

4. 2. Spin Dynamics and Magnetic Multilayers

   Author : Björn Skubic; Olle Eriksson; Lars Nordström; Mark D. Stiles; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; magnetism; electronic structure; density functional theory; spin dynamics; spin-transfer torque; spin-density wave; multilayer; interface structure; Fysik;

   Abstract : Theoretical studies based on first-principles theory are presented for a number of different magnetic systems. The first part of the thesis concerns spin dynamics and the second part concerns properties of magnetic multilayers. The theoretical treatment is based on electronic structure calculations performed by means of density functional theory. READ MORE

5. 3. Magnetization Dynamics in Nano-Contact Spin Torque Oscillators : Solitonic bullets and propagating spin waves

   Author : Stefano Bonetti; Johan Åkerman; Thomas Silva; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; magnetism; spintronics; thin magnetic films; spin transfer torque; magnetization dynamics; spin waves; microwave oscillators; giant magneto-resistance; Magnetism; Magnetism;

   Abstract : Magnetization dynamics in nano-contact spin torque oscillators (STOs) is investigated from an experimental and theoretical point of view. The fundamentals of magnetization dynamics due to spin transfer torque are given. A custom-made high frequency (up to 46 GHz) in large magnetic fields (up to 2. READ MORE

6. 4. Fabrication and Characterization of Nanocontact Spin-Torque Oscillators

   Author : Sohrab Redjai Sani; Johan Åkerman; Brad Engel; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spin-torque oscillators; phase locking; spin wave; giant magnetoresistance; spin transfer torque; thin films.;

   Abstract : The manufacturing of nanocontact-based spin-torque oscillators (NC-STOs)has opened the door for spintronic devices to play a part as active microwaveelements. The NC-STO has the capability of converting a direct current intoa microwave signal, and vice versa, by utilizing the spin transfer torque (STT)in ferromagnetic multilayer systems. READ MORE

7. 5. Magnetodynamics of pseudo spin valves investigated using co-planar waveguide and spin torque ferromagnetic resonance techniques

   Author : Masoumeh Fazlali; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Spintronics; Nanocontact pseudo spin valve; Spin waves; Oersted field; Interlayer exchange coupling; Acoustic and optical modes; Spin pumping; Spin transfer torque; Slonczewski mode; Collective mode;

   Abstract : Nanocontact spin-torque nano-oscillators (NC-STNOs), based on magnetic multilayers, can generate a wide range of highly nonlinear localized and propagating spin wave modes for use in magnonics. In this thesis, we study some aspects of these structures from the fundamental physics point of view using the spin torque ferromagnetic resonance technique (ST-FMR) and conventional broadband FMR technique. READ MORE