Sökning: "polarization"

Visar resultat 6 - 10 av 654 avhandlingar innehållade ordet polarization.

  1. 6. Polarization in the ELAIS-N1 LOFAR deep field

    Författare :Sara Piras; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ELAIS-N1; galaxies; polarization; polarimetric; radio continuum;

    Sammanfattning : The physical characteristics of cosmic magnetic fields are encoded in the po- larization properties of the extragalactic radio sources. Linearly polarized radiation undergoes Faraday rotation as it crosses a magneto-ionic medium; the rotation of the polarization angle of the signal is equal to its wavelength squared times the Rotation Measure (RM), that is proportional to the line- of-sight integral of the product of the magnetic field component along the line of sight and the density of thermal electrons. LÄS MER

  3. 7. Mode and Polarization Control in VCSELs using Surface Structures

    Författare :Åsa Haglund; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; single mode; dynamics; surface relief; Semiconductor laser; polarization; vertical-cavity surface-emitting laser; sub-wavelength grating; fabrication;

    Sammanfattning : The vertical-cavity surface-emitting laser (VCSEL) is a novel, low-cost light source with many attractive performance characteristics, such as low operating current, circular output beam, and high modulation bandwidth at low currents. This together with its easy integration into two-dimensional arrays has made it an established transmitter in short-distance single and parallel fiber-optical links, and new applications are continuously arising. LÄS MER

  4. 8. Tilted Foils Nuclear Spin Polarization and Measurement with Coulomb Excitation

    Författare :Hans Törnqvist; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Tilted; Foils; Polarization; Excitation; Coulomb; Nuclear; Spin;

    Sammanfattning : Developing new experimental tools is essential to expand the possibilites of probing the structure of atomic nuclei. The better the currently known properties of nuclei can be manipulated, the more information can be extracted from data collected in nuclear reaction experiments. LÄS MER

  5. 9. Diamond Devices Based on Valley Polarization

    Författare :Nattakarn Suntornwipat; Jan Isberg; Markus Gabrysch; Saman Majdi; Hitoshi Umezawa; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CVD diamond; valleytronics; Negative Differential Mobility; NDM; electron polarization; Time-of-Flight; magnetotransport; carrier transport; drift velocity; valley-transistor; Transferred-Electron Oscillator; TEO; TED; Gunn diode;

    Sammanfattning : Diamond is a wide bandgap semiconductor with extreme properties such as high thermal conductivity, high breakdown field, high carrier mobilities and chemical inertness. These properties together with the possibility to synthesize high purity Single-Crystalline (SC) diamond by Chemical Vapor Deposition (CVD), make it a very interesting material and a candidate for use in power electronics and in hazardous environments. LÄS MER

  7. 10. Polarization-Resolved Particle Holography

    Författare :Johan Öhman; Mikael Sjödahl; Erik Olsson; Per Bergström; Pietro Ferraro; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Experimentell mekanik; Experimental Mechanics;

    Sammanfattning : In this thesis, measurement of particle fields using digital holography is the main subject. The questions investigated consider positioning, identification and sizing of nanometer and micrometer particles. The thesis explore these topics using both simulations and experimental measurements. LÄS MER