Sökning: "tunable THz generation"

Hittade 5 avhandlingar innehållade orden tunable THz generation.

  1. 1. Photonic Techniques for Real-Time Analog-to-Digital Conversion

    Författare :Johan Stigwall; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tunable THz generation; photonic time-stretch; photonic sampling; Photonic analog-to-digital conversion; optical signal processin; photonic binary encoding; microwave photonics; photonic thresholding;

    Sammanfattning : All-electronic analog-to-digital conversion (ADC) technology is limited by the timing accuracy and inherent speed of semiconductor materials. Photonic techniques, however, can potentially enable real-time ADC at a considerably wider bandwidth, higher sample rate and/or resolution, thanks to the availability of extremely accurate optical clocks and the immense bandwidth of optical systems. LÄS MER

  3. 2. Single-cycle undulator light

    Författare :Georgii Shamuilov; Vitaliy Goryashko; Gianluca Geloni; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; terahertz technology; light sources; electron beams; space charge; waveform control; optical magnetic lens; Fysik; Physics;

    Sammanfattning : The past decade has witnessed a sharp rise of interest in coherent terahertz (THz) light sources for applications in condensed-matter physics. These sources are a powerful tool for studying collective excitations in solid-state systems: THz light can directly couple to low-energy excitations on the meV-scale such as the collective excitations of spins and phonons. LÄS MER

  4. 3. Backward and Forward Nonlinear Optical Processes in Potassium Titanyl Phosphate

    Författare :Kjell Martin Mølster; Fredrik Laurell; Valdas Pasiskevicius; Ulf L. Österberg; Stefano Taccheo; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; QPM; PPKTP; Nonlinear Optics; Backward second-harmonic; BWOPO; OPO; parametric devices; QPM; Ickelinär Optik; BWOPO; OPO; PPKTP; QPM; kvasifasematching; ikkelinæer optikk; bakovervendt parametrisk oscillator; optisk parametrisk oscillator; PPKTP; Optics and Photonics; Optik och fotonik; Physics; Fysik;

    Sammanfattning : Second-order nonlinear optical processes generate radiation across a broad spectrum, including UV and the far-infrared. In this thesis, new light sources in the near(NIR) and mid infrared (MIR) using three-wave mixing geometries in periodically poled potassium titanyl phosphate (PPKTP) is studied. LÄS MER

  5. 4. Tailored fiber lasers and their use in nonlinear optics

    Författare :Peter Zeil; Fredrik Laurell; Andy Clarkson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

    Sammanfattning : The objective of this thesis work was to develop tailored fiber lasers, which meet the pump requirement for efficient continuous-wave (cw) frequency conversion to the visible and the mid-infrared wavelength regimes: a stable, high-power, wavelength-tunable, narrow-linewidth output in a single polarization. As a first step, the prospect of tuning ytterbium fiber lasers over an unprecedented wavelength range, from 980nm to 1100nm, was investigated. LÄS MER

  7. 5. Energy scaling of infrared nanosecond optical parametric oscillators and amplifiers based on Rb:KTiOPO4

    Författare :Riaan Stuart Coetzee; Valdas Pasiskevicius; Gunnar Rustad; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

    Sammanfattning : High-energy, narrowband, nanosecond pulsed mid-infrared sources centred on 2 μm are requiredin applications in remote sensing, standoff detection and pollution monitoring using LIDARs.Currently, space-borne LIDAR missions are under development by major space agencies aroundthe world for active measurements of the atmospheric gas constituents and their dynamics. LÄS MER