Sökning: "magnetic nanostructures"

Visar resultat 1 - 5 av 51 avhandlingar innehållade orden magnetic nanostructures.

1. 1. Magnetoplasmonic nanostructures

   Författare :Emil Melander; Vassilios Kapaklis; Björgvin Hjörvarsson; Evangelos Th. Papaioannou; Paolo Vavassori; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Magnetism; nanostructures; plasmons; magneto-optics; magnetoplasmonics; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : Surfaces that are nanopatterned, metallic, and magnetic can support surface plasmon resonances, providing an alternative and effective way to reconfigure flat optical components. Utilising a range of near- and far-field characterisation techniques, the optical and magneto-optical properties of lithographically patterned thin magnetic films are investigated. LÄS MER

3. 2. Modulating magnetic interactions : in metamaterials and amorphous alloys

   Författare :Nanny Strandqvist; Björgvin Hjörvarsson; Alexei Vorobiev; Sean Langridge; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetic metamaterials; interlayer exchange coupling; superlattice; mesospins; magnetic nanostructures; emergence; amorphous alloys; CoAlZr; FeZr; Fysik; Physics;

   Sammanfattning : This thesis is focused on exploring and modulating magnetic interactions in metamaterials and amorphous alloys along one-, two-, and three-dimensions. First, thin films of alternating Fe and MgO are adapted to modulate magnetic interactions along one dimension. LÄS MER

4. 3. Phase transitions in magnetic metamaterials

   Författare :Björn Erik Skovdal; Björgvin Hjörvarsson; Vassilios Kapaklis; Gunnar K. Pálsson; Peter Schiffer; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetic metamaterials; artificial spin ice; mesospins; magnetic nanostructures; mesoscopic spin systems; multiscale materials; tri-criticality; emergence; edge modes;

   Sammanfattning : Magnetic metamaterials consisting of arrays of densely packed, two-dimensional nanoscale magnetic islands have degrees of freedom on two separate length scales: inside the islands, and among them. These degrees of freedom can be tuned by e.g. size, shape, island separation and lattice geometry. LÄS MER

5. 4. Designing order with long-range interactions in mesoscopic magnetic chains

   Författare :Christina Vantaraki; Vassilios Kapaklis; Björgvin Hjörvarsson; Gabriella Andersson; Tapati Sarkar; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetism; mesospins; mesoscopic magnetic chains; magnetic nanostructures; long-range interactions;

   Sammanfattning : This thesis investigates how the low-energy magnetic configuration of a mesoscopic chain can be tuned by geometrical modifications. The magnetic arrays made by single-domain stadium shaped elements positioned side-by-side were fabricated by patterning into a sputtered ferromagnetic thin film. LÄS MER

7. 5. Design, Synthesis And Characterization Of Magnetic Ferrite Nanostructures : Toward Novel Permanent Magnets

   Författare :Pierfrancesco Maltoni; Roland Mathieu; Adrian Quesada; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nanosystems; magnetic interactions; magnetism; ferrites; materials science; Engineering Science with specialization in Solid State Physics; Teknisk fysik med inriktning mot fasta tillståndets fysik;

   Sammanfattning : Magnetic oxide nanoparticles (NPs) may interact with each-other for example via dipolar or superexchange interactions, depending whether they are in direct contact. These interparticle interactions yield both ferro- and/or antiferromagnetic coupling and modify the energy barrier of the magnetic particle, depending upon the strength of the coupling and orientation of the particles. LÄS MER