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Showing result 1 - 5 of 54 swedish dissertations matching the above criteria.

  2. 1. Generation and Applications of Picosecond Pulses in High-Capacity Fiber Optic Systems

    Author : Jie Li; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear distortion; optical pulse shaping; dispersion-management; eye-diagram; cross-phase modulation; optical sampling; optical fiber applications; multiplexing; parametric amplification; demultiplexing; optical pulses; fiber optical communication; nonlinear systems; time division multiplexing; four-wave mixing; polarization-mode dispersion; optical signal processing; fiber optical nonlinearities; fiber ring laser; soliton robustness; mode-locking; optical filters; networks;

    Abstract : This thesis deals with short optical pulse generation from actively mode-locked Erbium-doped fiber ring lasers (ML-EFRL) and their applications in all-optical signal processing (optical sampling and switching) and transmission experiments for high-capacity fiber optic systems. In future ultra-high bit-rate optical time division multiplexed (OTDM) systems, one of the key requirements is to develop reliable optical pulse sources that can generate high quality optical pulses. READ MORE

  4. 2. Material and technique development for ultrasound optical tomography using spectral hole burning filters

    Author : Alexander Bengtsson; NanoLund: Centre for Nanoscience; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biomedical imaging; ultrasound optical tomography; acousto-optical tomography; rare-earth-ion doped crystals; spectral holeburning; slow light filters; Tm 3:LaF3; Fysicumarkivet A:2022:Bengtsson;

    Abstract : The molecular sensitivity provided by optical photons has potential advantages in medical diagnostics, for example, in distinguishing healthy from cancerous tissue. However, scattering resulting from inhomogeneities in the refractive index of tissues prevents spatially resolved optical measurements in biological material, except at very shallow depths. READ MORE

  5. 3. Generation and Transmission of Optical Solitons at Ultrahigh Bit Rates

    Author : Bamdad Bakhshi; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear optics; chirp-free optical pulses; lowpass filtering; polarization-maintaining fibers; optical communication; optical solitons; Erbium fiber ring laser; dispersion-management; active mode-locking; soliton interactions; erbium-doped fiber amplifier; Gaussian pulses;

    Abstract : This thesis deals with the generation and transmission of optical solitons in ultrahigh-speed fiber-optic communication systems. For optical soliton pulses the fiber dispersion and nonlinearity can under certain circumstances cancel each other, thus allowing the solitons to remain undistorted over long distances. READ MORE

  6. 4. Nanostructured Semiconductor Materials for Light Manipulation Functions

    Author : Dennis Visser; Srinivasan Anand; Alvaro Blanco; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; semiconductor materials; c-Si; a-Si; GaInP; TiO2; ZnO; nanostructuring; light manipulation functions; top-down fabrication; embossing; FDTD simulations; nanowires; nanopillars; nanodisks; microcones; optical response; reflectance; transmittance; absorbance; spectrophotometry; photoluminescence; Mie resonators; mode coupling; broadband anti-reflection; light extraction enhancement; optical sensing; optical color filters; color conversion; Optik och fotonik; Optics and Photonics;

    Abstract : Structuring of semiconductor materials is utilized in many optoelectronic devices, e.g, in order to make them more efficient, cost-effective, and/or to obtain specific wavelength-engineered responses. Semiconductor materials are widely used in optoelectronic devices due to their favorable optical and electric properties. READ MORE

  7. 5. Development of Models, Methods, and Materiel for Deep Tissue Imaging using Light, Ultrasound, and Spectral-Hole Burning

    Author : David Hill; NanoLund: Centre for Nanoscience; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biomedical imaging; ultrasound optical tomography; ultrasound-modulated optical tomography; acousto-optical tomography; Monte Carlo light transport; spectral-hole-burning filters; rare-earth-ion doped crystals; stoichiometric lithium niobate;

    Abstract : The medical imaging technique called “ultrasound optical tomography” (UOT) entails light scattered in tissue that is given spatial information by interacting with an ultrasound field, thus allowing for molecular information to be imaged with ultrasonic resolution. This thesis discusses how UOT can be implemented, with most attention put toward the implementation using spectral-hole-burning filters (SHF) in rare-earth-ion-doped crystals. READ MORE