Sökning: "Terahertz radiation generation"

Hittade 3 uppsatser innehållade orden Terahertz radiation generation.

  1. 1. Towards a setup for narrowband terahertz generation through difference-frequency mixing of chirped ultrashort pulses

    Master-uppsats, Lunds universitet/Atomfysik; Lunds universitet/Fysiska institutionen

    Författare :Isa Clementsson; [2023]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : Terahertz radiation is a useful tool for inducing lower-energy excitations in matter, where it can be used to cause structural changes through direct interaction with the crystal lattice. Sub-picosecond optical pulses can be used to generate intense broadband terahertz pulses through optical rectification in nonlinear crystals, reaching peak electric fields of several MV/m and conversion efficiencies as high as a few percent. LÄS MER

  3. 2. Time-resolved x-ray diffraction study of longitudinal optical phonons in zincblende semiconductors

    Master-uppsats, Lunds universitet/Atomfysik; Lunds universitet/Fysiska institutionen

    Författare :Lassi Linnala; [2022]
    Nyckelord :femtosecond THz radiation; ultrafast x-ray diffraction; pump-probe; longitudinal optical phonons; zincblende semiconductors; anharmonic decay; density functional perturbation theory; Physics and Astronomy;

    Sammanfattning : Anharmonic decay of longitudinal optical (LO) phonons in zincblende semiconductors is not at present well characterized due to the polar and many-body nature of the problem. Femtosecond THz radiation offers a novel route to this study, as the interaction of this radiation is directly with the phonon lattice and these THz excited phonons do not have enough energy to excite electrons over the band gap. LÄS MER

  4. 3. Characterization of Terahertz Radiation Generated in an Organic Crystal

    Master-uppsats, Lunds universitet/Atomfysik; Lunds universitet/Fysiska institutionen

    Författare :Åsa Bengtsson; [2016]
    Nyckelord :Nonlinear optics; Terahertz radiation generation; Optical rectification; Difference frequency generation; Organic crystal; DSTMS; Physics and Astronomy;

    Sammanfattning : The terahertz region of the electromagnetic spectrum is an important research area allowing insights into fundamental science such as inter-molecular interactions, and with applications in the environmental, medical and security field. Using femtosecond lasers, it is possible to design compact and efficient terahertz generation schemes, resulting in few-cycle broadband pulses. LÄS MER