Sökning: "ferroelectric domains"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden ferroelectric domains.

  1. 1. Ferroelectric domain engineering and characterization for photonic applications

    Författare :Simonetta Grilli; Fredrik Laurell; Wolfgang Sohler; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; LiNbO; KTiOPO; interferometry; digital holography; electric field poling; electro-optic materials; holographic lithography; ferroelectric domains; nanostructures; microstructures; Optical physics; Optisk fysik;

    Sammanfattning : Lithium niobate (LiNbO3) and KTiOPO4 (KTP) are ferroelectric crystals of considerable interest in different fields of optics and optoelectronics. Due to its large values of the nonlinear optical, electro-optic (EO), piezoelectric and acousto-optical coefficients, LiNbO3 is widely used for laser frequency conversion using the quasiphase matching (QPM) approach where the sign of nonlinearity has been periodically modulated by electric field poling (EFP). LÄS MER

  2. 2. Domain engineering in KTiOPO4

    Författare :Carlota Canalias; Fredrik Laurell; Benoît Boulanger; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; quasi-phase matching; KTiOPO4; ferroelectric domains; atomic force microscopy; periodic electric field poling; polarization switching; second harmonic generation; Optical physics; Optisk fysik;

    Sammanfattning : Ferroelectric crystals are commonly used in nonlinear optics for frequency conversion of laser radiation. The quasi-phase matching (QPM) approach uses a periodically modulated nonlinearity that can be achieved by periodically inverting domains in ferroelectric crystals and allows versatile and efficient frequency conversion in the whole transparency region of the material. LÄS MER

  3. 3. Characterization of domain switching and optical damage properties in ferroelectrics

    Författare :Junji Hirohashi; Fredrik Laurell; Ady Arie; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; quasi-phase matching; ferroelectric domains; stoichiometric LiNbO3; stoichiometric LiTaO3; KTiOPO4; KNbO3; polarization switching; periodic electric field poling; optical damages; Optical physics; Optisk fysik;

    Sammanfattning : Nonlinear optical frequency conversion is one of the most important key techniques in order to obtain lasers with wavelengths targeted for specific applications. In order to realize efficient and tailored lasers, the quasi-phase-matching (QPM) approach using periodically-poled ferroelectric crystals is getting increasingly important. LÄS MER

  4. 4. Engineering ferroelectric domains and charge transport by proton exchange in lithium niobate

    Författare :Michele Manzo; Katia Gallo; Marin Alexe; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Lithium niobate; Ferroelectrics; Materials Science and Engineering; Teknisk materialvetenskap; Physics; Fysik;

    Sammanfattning : Ferroelectrics are dielectric materials possessing a switchable spontaneous polarization, which have attracted a growing interest for a broad variety of applications such as ferroelectric lithography, artificial photosynthesis, random and dynamic access memories (FeRAMs and DRAM), but also for the fabrication of devices for nonlinear optics, etc. All the aforementioned applications rely on the control of the ferroelectric domains arrangement, or the charge distribution and transport. LÄS MER

  5. 5. Advanced nano- and microdomain engineering of Rb-doped KTiOPO4 for nonlinear optical applications

    Författare :Charlotte Liljestrand; Carlota Canalias; Sunao Kurimura; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; KTiOPO4; nonlinear optics; MOPO; quasi-phase matching; SHG; ferroelectrics; domain structuring; periodic poling; Physics; Fysik;

    Sammanfattning : Fine-pitch ferroelectric domain gratings are extensively used for generation of light in the visible and near-infrared spectral regions through quasi-phase matched (QPM) frequency conversion. Sub-μm QPM devices enables demonstration of nonlinear optics with counterpropagating waves, a field of nonlinear optics which remains sparsely explored due to the difficulty of fabricatinghigh quality gratings. LÄS MER