Sökning: "Spin pumping"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden Spin pumping.

1. 1. Nanoscale spin dynamics in ferromagnetic/normal-metal heterostructures for spin-logic application : Engineering of spin-torque efficiency in Co2FeAl/β-Ta and Ru/FeCo/Ru multi-layers

   Författare :Rahul Gupta; Peter Svedlindh; Danny Thonig; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spintronics; spin pumping; spin dynamics; ferromagnetic resonance; magnetic thin films; heterostructure; spin-logic; spin-mixing conductance; Engineering Science with specialization in Solid State Physics; Teknisk fysik med inriktning mot fasta tillståndets fysik; Teknisk fysik med inriktning mot materialvetenskap; Engineering Science with specialization in Materials Science; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : In the present information age, people across the globe generate an enormous digital footprint. Therefore, it is necessary to store and process the information in an elegant way. Spin-logic circuits are being considered potential candidates beyond CMOS integrated computing due to high clock speed, non-volatility, and higher logical efficiency. LÄS MER

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

   Författare :Masoumeh Fazlali; Göteborgs universitet; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

4. 3. Electron and Proton Transfer in Nitric Oxide Reductase : NO Binding, NO Reduction and no Pumping

   Författare :Peter Lachmann; Pia Ädelroth; Peter Brzezinski; Fahmi Himo; Stockholms universitet; []
   Nyckelord :Flow-Flash; Nitric Oxide Reductase; Heme Copper Oxidase;

   Sammanfattning : Nitric oxide reductase (NOR) from Paracoccus denitrificans catalyzes the two electronreduction of NO to N2O (2NO + 2H+ + 2e- → N2O + H2O) as part of the process ofdenitrification, the step-wise reduction of nitrate to dinitogen. The NOR-catalyzedreaction is central in the nitrogen cycle, since in this step the N=N double bond isformed. LÄS MER

5. 4. Ultrafast spin dynamics and relaxation in metallic ferromagnets

   Författare :Vivek Unikandanunni; Stefano Bonetti; Olof Karis; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetization dynamics; Three temperature model; Cobalt; Anisotropy; Electron-phonon coupling; THz; Platinum; Silver; fysik; Physics;

   Sammanfattning : We performed ultrafast demagnetization measurements on epitaxial hcp-cobalt thin film with the easy axis in the plane of the film by pumping the sample with 400 nm radiation and probing the magneto-optic effects in the longitudinal magneto optic Kerr effect geometry using 800 nm radiation. The in-plane magnetic anisotropy of the sample enabled us to measure the demagnetization dynamics along two different crystalline directions, namely along the easy axis and at 45 degrees between the easy and hard axes. LÄS MER

7. 5. Transport Studies of Local-Gate Defined Quantum Dots in Nanowires

   Författare :Carina Fasth; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Semiconductory physics; Fysik; Physics; quantum devices; nanowire; quantum dot; Halvledarfysik;

   Sammanfattning : This thesis focuses on electrical transport in semiconductor InAs nanowires grown by chemical beam epitaxy. Initially, transport length scales of homogeneous InAs n-type nanowires are characterized by low-temperature magnetoconductance measurements. The measurements show phase-coherent conductivity corrections. LÄS MER