Sökning: "Giant Magnetoresistance"
Visar resultat 1 - 5 av 12 avhandlingar innehållade orden Giant Magnetoresistance.
1. Spin momentum transfer effects for spintronic device applications
Sammanfattning : The recent discovery that a spin-polarized current can exert a large torque on a ferromagnet, through direct transfer of spin angular momentum, offers the possibility of electrical current controlled manipulation of magnetic moment in nanoscale magnetic device structures. This so-called spin torque effect holds great promise for two applications, namely, spin torque oscillators (STOs) for wireless communication and radar communication, and spin transfer torque RAM (STT-RAM) for data/information storage. LÄS MER
2. Fabrication and Characterization of Nanocontact Spin-Torque Oscillators
Sammanfattning : 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. LÄS MER
3. Single-Electron Tunneling Spectroscopy in Magnetic Nanoparticles and Molecular Magnets
Sammanfattning : This thesis deals with single-electron tunneling in transistor-like devices in which the central electrode is either a metal nanoparticle (possibly ferromagnetic) or a molecular magnet. The investigated systems split into two different categories, depending on the size of the central island. LÄS MER
4. Magnetization Dynamics in Nano-Contact Spin Torque Oscillators : Solitonic bullets and propagating spin waves
Sammanfattning : 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. LÄS MER
5. Spin-diode effect and thermally controlled switching in magnetic spin-valves
Sammanfattning : This thesis demonstrates two new device concepts that are based on the tunneling and giant magnetoresistance effects. The first is a semiconductor-free asymmetric magnetic double tunnel junction that is shown to work as a diode, while at the same time exhibiting a record high magnetoresistance. LÄS MER