Sökning: "vacuum magnetization"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden vacuum magnetization.

1. 1. QED with external fields : vacuum effects and thermodynamics

   Författare :Per Liljenberg; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; density; QED; vacuum magnetization; unstable vacuum; finite temperature; external field; boson stars; relativistic Bose gas;

   Sammanfattning : .... LÄS MER

3. 2. Constructing and Commissioning HELIOS – A High Harmonic Generation Source for Pump-Probe Measurements with sub 50 fs Temporal Resolution : The Development of Experimental Equipment for Extreme Ultraviolet Spectroscopy

   Författare :Joachim A. Terschlüsen; Johan Söderström; Margaret Murnane; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Angle-resolved photoemission spectroscopy; Angle resolved photoemission spectroscopy; Angle-resolved time-of-flight; Angle resolved time of flight; ARTOF; ARPES; tr-ARPES; fs; fs resolution; Fourier transform spectrometer; Fourier-transform spectrometer; Fourier transform spectroscopy; Fourier-transform spectroscopy; FTS; gas cell; high harmonic generation; laser; liquid jet; monochromator; HELIOS; HHG; off-plane mount; off plane mount; OPA; optical parametric amplifier; PCPDTBT; pulse shaping; pump probe; pump-probe measurements; pump-probe measurements; pump-probe spectroscopy; pump-probe spectroscopy; Rowland spectrometer; time-of-flight spectrometer; time of flight spectrometer; TOF; time-resolved spectroscopy; time resolved spectroscopy; time-resolved experiments; time resolved experiments; T-MOKE; tr-PES; PES; photoelectron spectroscopy; transverse magneto optical Kerr effect; transverse magneto-optical Kerr effect; ultrafast; ultra-high vacuum; ultra high vacuum; UHV; XUV; VUV; X-rays; Permalloy; magnetization dynamic; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : This thesis presents HELIOS, an in-house laboratory for time-resolved pump-probe spectroscopy with extreme-ultraviolet (XUV) probe radiation. A wide span of pump wavelengths can be generated using commercial laser equipment while XUV probe radiation is generated via a high harmonic generation process in a noble gas delivering probe photons with energies between 20 eV and 72 eV. LÄS MER

4. 3. Enhanced Polarizing Neutron Optics with 11B4C Incorporation : SLD Tunability, Interface Refinement, and Elimination of Magnetic Coercivity

   Författare :Anton Zubayer; Fredrik Eriksson; Jens Birch; Naureen Ghafoor; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : This thesis explores novel strategies for improving Fe-based polarizing neutron optics, a critical part for improving neutron scattering methods to study materials science, physics, biology, medicine, chemistry and cultural heritage. Polarization analysis is important in uncovering data on magnetic domains, protein structures, molecular composition and orientation in biological systems, and ion-diffusion mechanisms that would otherwise be inaccessible. LÄS MER

5. 4. Hot and Dense Gauge Theories with External Fields

   Författare :David Persson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : In the introductory part of this thesis, I briefly review quantum statistichal mechanics; quantum field theory with external fields; the real and imaginary time formalisms in thermal field theory; and the hard thermal loop resummation. In the second part, consisting of here reprinted research articles, we apply this to quantum electrodynamics and quantum chromodynamics with a background (chromo-) magnetic field in the presence of a heat and charge reservoir. LÄS MER

7. 5. Magnetic Heterostructures : The Effect of Compositional Modulation on Magnetic Properties

   Författare :Inna Soroka; Roger Wäppling; Björgvin Hjörvarsson; Rudolf Schäfer; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Magnetism; Sputter deposition; Superlattice; Multilayers; Materialvetenskap; Materials science; Teknisk materialvetenskap;

   Sammanfattning : The effect of compositional modulation on structural and magnetic properties of magnetic heterostructures was explored. The systems under focus were ferromagnetic superlattices Fe81Ni19/Co, metal-insulator multilayers Al2O3/Ni81Fe19, nanoparticles and artificial multilayered pillars. LÄS MER