@article{57619,
  abstract     = {{<jats:p>Ferroelectric liquid crystals exhibiting a chiral smectic C* phase are deposited on z cut periodically poled lithium niobate substrates and investigated by polarized optical microscopy. While the pure substrates placed between crossed polarizers and observed in transmission appear dark, uniformly aligned liquid crystal films deposited on these substrates show alternating domains with varying brightness. This effect can be attributed to the well-known coupling between the direction of the spontaneous polarization and the optical axis in the birefringent ferroelectric smectic C* phase. Quantitative measurements of the tilt angle between the local optical axis and the smectic layer normal confirm antiparallel orientations of spontaneous polarization of the liquid crystal from domain to domain, as expected by the periodic poling of the lithium niobate substrate. This effect provides a valuable non-destructive method of optical inspection of the quality of periodically poled ferroelectric substrates, which plays an important role in achieving quasi-phase-matching in non-linear optical applications.</jats:p>}},
  author       = {{Meier, Patrick A. and Keuker-Baumann, Susanne and Röder, Thorsten and Herrmann, Harald and Ricken, Raimund and Silberhorn, Christine and Kitzerow, Heinz-Siegfried}},
  issn         = {{1896-3757}},
  journal      = {{Opto-Electronics Review}},
  pages        = {{150611--150611}},
  publisher    = {{Polish Academy of Sciences Chancellery}},
  title        = {{{Optical imaging of ferroelectric domains in periodically poled lithium niobate using ferroelectric liquid crystals}}},
  doi          = {{10.24425/opelre.2024.150611}},
  year         = {{2024}},
}

@article{57618,
  abstract     = {{<jats:p>The presence of a polymer network and/or the addition of ferroelectric nanoparticles to a nematic liquid crystal are found to lower transition temperatures and birefringence, which indicates reduced orientational order. In addition, the electro-optic switching voltage is considerably increased when a polymer network is formed by in situ polymerization in the nematic state. However, the resulting polymer network liquid crystal switches at similar voltages as the neat liquid crystal when polymerization is performed at an elevated temperature in the isotropic state. When nanoparticle dispersions are polymerized at an applied DC voltage, the transition temperatures and switching voltages are reduced, yet they are larger than those observed for polymer network liquid crystals without nanoparticles polymerized in the isotropic phase.</jats:p>}},
  author       = {{Nordendorf, Gaby and Jünnemann-Held, Gisela and Lorenz, Alexander and Kitzerow, Heinz-Siegfried}},
  issn         = {{2079-4991}},
  journal      = {{Nanomaterials}},
  number       = {{11}},
  publisher    = {{MDPI AG}},
  title        = {{{Effects of Composition and Polymerization Conditions on the Electro-Optic Performance of Liquid Crystal–Polymer Composites Doped with Ferroelectric Nanoparticles}}},
  doi          = {{10.3390/nano14110961}},
  volume       = {{14}},
  year         = {{2024}},
}

@article{57616,
  author       = {{Becker, David and Meier, Patrick and Kuhlmann, Andreas and Sternemann, Christian and Bock, Harald and Steinrück, Hans-Georg and Kitzerow, Heinz-Siegfried}},
  issn         = {{2637-6113}},
  journal      = {{ACS Applied Electronic Materials}},
  number       = {{2}},
  pages        = {{1234--1243}},
  publisher    = {{American Chemical Society (ACS)}},
  title        = {{{Influence of the Deposition Rate on the Alignment and Performance of Perylene-3,4,9,10-tetracarboxylic Tetraethyl Ester in an Organic Light Emitting Diode}}},
  doi          = {{10.1021/acsaelm.3c01586}},
  volume       = {{6}},
  year         = {{2024}},
}

@article{57620,
  author       = {{Zhang, Bingru and Martens, Kevin and Kneer, Luisa and Nguyen, Linh and Kempter, Susanne and Huber, Klaus and Kitzerow, Heinz-Siegfried}},
  issn         = {{1542-1406}},
  journal      = {{Molecular Crystals and Liquid Crystals}},
  pages        = {{1--9}},
  publisher    = {{Informa UK Limited}},
  title        = {{{Investigation of nano-rods fabricated by the DNA origami method using static and dynamic light scattering}}},
  doi          = {{10.1080/15421406.2024.2418067}},
  year         = {{2024}},
}

@article{57625,
  author       = {{Giesselmann, Frank and Kitzerow, Heinz-Siegfried and Zentel, Rudolf}},
  issn         = {{1358-314X}},
  journal      = {{Liquid Crystals Today}},
  number       = {{1}},
  pages        = {{2--9}},
  publisher    = {{Informa UK Limited}},
  title        = {{{Fifty years of liquid crystal research in the mirror of the German Liquid Crystal Conference}}},
  doi          = {{10.1080/1358314x.2024.2415787}},
  volume       = {{33}},
  year         = {{2024}},
}

@article{49609,
  abstract     = {{<jats:p>The alignment of liquid crystals on surfaces plays a central role in optimizing their performances. In this work, a cutting-edge nano-lithography-based method to control the local orientation of a thermotropic liquid crystal is applied to easily available commercial standard materials and evaluated. Parallel nanogrooves on a substrate, created through 3D nanoprinting in a negative-tone photoresin optimized for two-photon polymerization are used for this purpose. Azimuthal anchoring energies of the order from 10<jats:sup>−6</jats:sup> J/m<jats:sup>2</jats:sup> to 10<jats:sup>−5</jats:sup> J/m<jats:sup>2</jats:sup> are found, depending on the spacing, width and depth of the grooves. In part, these values are larger than those reported previously for another photopolymer. Both uniform alignment and spatial patterns of different alignment directions can be realized. Electro-optic studies confirm the suitability of the method for electrically addressable photonic applications and indicate strong polar anchoring.</jats:p>}},
  author       = {{Zhang, Bingru and Plidschun, Malte and Schmidt, Markus A. and Kitzerow, Heinz-Siegfried}},
  issn         = {{2159-3930}},
  journal      = {{Optical Materials Express}},
  keywords     = {{Electronic, Optical and Magnetic Materials}},
  number       = {{12}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{Anchoring and electro-optic switching of liquid crystals on nano-structured surfaces fabricated by two-photon based nano-printing}}},
  doi          = {{10.1364/ome.503100}},
  volume       = {{13}},
  year         = {{2023}},
}

@article{43440,
  author       = {{Zhang, Bingru and Nguyen, Linh and Martens, Kevin and Heuer-Jungemann, Amelie and Philipp, Julian and Kempter, Susanne and Rädler, Joachim O. and Liedl, Tim and Kitzerow, Heinz-Siegfried}},
  issn         = {{0267-8292}},
  journal      = {{Liquid Crystals}},
  keywords     = {{Condensed Matter Physics, General Materials Science, General Chemistry}},
  number       = {{7-10}},
  pages        = {{1243--1251}},
  publisher    = {{Informa UK Limited}},
  title        = {{{Luminescent DNA-origami nano-rods dispersed in a lyotropic chromonic liquid crystal}}},
  doi          = {{10.1080/02678292.2023.2188494}},
  volume       = {{50}},
  year         = {{2023}},
}

@article{40513,
  abstract     = {{Geometric-phase dielectric meta-lenses made of silicon with high numerical aperture and short focal lengths are fabricated and characterised. For circularly polarised light, the same meta-lens can act as a converging or diverging lens, depending on the handedness of the circular polarisation. This effect enables application for optical tweezers that trap or release µm-size polymer beads floating in a microfluidic channel on demand. An electrically addressable polarisation converter based on liquid crystals may be used to switch between the two states of polarisation, at which the light transmitted through the meta-lens is focused (trapping) or defocussed (releasing), respectively.}},
  author       = {{Geromel, René and Rennerich, Roman and Zentgraf, Thomas and Kitzerow, Heinz-Siegfried}},
  journal      = {{Liquid Crystals}},
  number       = {{7-10}},
  pages        = {{1193--1203}},
  publisher    = {{Taylor & Francis}},
  title        = {{{Geometric-phase metalens to be used for tunable optical tweezers in microfluidics}}},
  doi          = {{10.1080/02678292.2023.2171146}},
  volume       = {{50}},
  year         = {{2023}},
}

@article{39653,
  abstract     = {{<jats:title>Abstract</jats:title><jats:p>A detailed investigation of the energy levels of perylene-3,4,9,10-tetracarboxylic tetraethylester as a representative compound for the whole family of perylene esters was performed. It was revealed via electrochemical measurements that one oxidation and two reductions take place. The bandgaps determined via the electrochemical approach are in good agreement with the optical bandgap obtained from the absorption spectra via a Tauc plot. In addition, absorption spectra in dependence of the electrochemical potential were the basis for extensive quantum-chemical calculations of the neutral, monoanionic, and dianionic molecules. For this purpose, calculations based on density functional theory were compared with post-Hartree–Fock methods and the CAM-B3LYP functional proved to be the most reliable choice for the calculation of absorption spectra. Furthermore, spectral features found experimentally could be reproduced with vibronic calculations and allowed to understand their origins. In particular, the two lowest energy absorption bands of the anion are not caused by absorption of two distinct electronic states, which might have been expected from vertical excitation calculations, but both states exhibit a strong vibronic progression resulting in contributions to both bands.</jats:p>}},
  author       = {{Wiebeler, Christian and Vollbrecht, Joachim and Neuba, Adam and Kitzerow, Heinz-Siegfried and Schumacher, Stefan}},
  issn         = {{2045-2322}},
  journal      = {{Scientific Reports}},
  keywords     = {{Multidisciplinary}},
  number       = {{1}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Unraveling the electrochemical and spectroscopic properties of neutral and negatively charged perylene tetraethylesters}}},
  doi          = {{10.1038/s41598-021-95551-0}},
  volume       = {{11}},
  year         = {{2021}},
}

@article{16301,
  author       = {{Atorf, Bernhard and Mühlenbernd, Holger and Zentgraf, Thomas and Kitzerow, Heinz-Siegfried}},
  issn         = {{1094-4087}},
  journal      = {{Optics Express}},
  number       = {{6}},
  pages        = {{8898--8908}},
  title        = {{{All-optical switching of a dye-doped liquid crystal plasmonic metasurface}}},
  doi          = {{10.1364/oe.383877}},
  volume       = {{28}},
  year         = {{2020}},
}

@article{35869,
  author       = {{Keum, Changmin and Becker, David and Archer, Emily and Bock, Harald and Kitzerow, Heinz-Siegfried and Gather, Malte C. and Murawski, Caroline}},
  issn         = {{2195-1071}},
  journal      = {{Advanced Optical Materials}},
  keywords     = {{Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials}},
  number       = {{17}},
  publisher    = {{Wiley}},
  title        = {{{Organic Light‐Emitting Diodes Based on a Columnar Liquid‐Crystalline Perylene Emitter}}},
  doi          = {{10.1002/adom.202000414}},
  volume       = {{8}},
  year         = {{2020}},
}

@article{35859,
  author       = {{Risse, Anna Margareta and Schmidtke, Jürgen and Kitzerow, Heinz-Siegfried}},
  issn         = {{0267-8292}},
  journal      = {{Liquid Crystals}},
  keywords     = {{Condensed Matter Physics, General Materials Science, General Chemistry}},
  number       = {{7}},
  pages        = {{1025--1033}},
  publisher    = {{Informa UK Limited}},
  title        = {{{Dynamics of a liquid crystal-based modulator with germanium substrates for mid-infrared radiation}}},
  doi          = {{10.1080/02678292.2020.1839803}},
  volume       = {{48}},
  year         = {{2020}},
}

@article{35868,
  abstract     = {{<jats:p>Rod-like and sheet-like nano-particles made of desoxyribonucleic acid (DNA) fabricated by the DNA origami method (base sequence-controlled self-organized folding of DNA) are dispersed in a lyotropic chromonic liquid crystal made of an aqueous solution of disodium cromoglycate. The respective liquid crystalline nanodispersions are doped with a dichroic fluorescent dye and their orientational order parameter is studied by means of polarized fluorescence spectroscopy. The presence of the nano-particles is found to slightly reduce the orientational order parameter of the nematic mesophase. Nano-rods with a large length/width ratio tend to preserve the orientational order, while more compact stiff nano-rods and especially nano-sheets reduce the order parameter to a larger extent. In spite of the difference between the sizes of the DNA nano-particles and the rod-like columnar aggregates forming the liquid crystal, a similarity between the shapes of the former and the latter seems to be better compatible with the orientational order of the liquid crystal.</jats:p>}},
  author       = {{Zhang, Bingru and Martens, Kevin and Kneer, Luisa and Funck, Timon and Nguyen, Linh and Berger, Ricarda and Dass, Mihir and Kempter, Susanne and Schmidtke, Jürgen and Liedl, Tim and Kitzerow, Heinz-Siegfried}},
  issn         = {{2079-4991}},
  journal      = {{Nanomaterials}},
  keywords     = {{General Materials Science, General Chemical Engineering}},
  number       = {{9}},
  publisher    = {{MDPI AG}},
  title        = {{{DNA Origami Nano-Sheets and Nano-Rods Alter the Orientational Order in a Lyotropic Chromonic Liquid Crystal}}},
  doi          = {{10.3390/nano10091695}},
  volume       = {{10}},
  year         = {{2020}},
}

@article{13870,
  author       = {{Atorf, Bernhard and Auf der Landwehr, Chris Holm and Rennerich, Roman and Kitzerow, Heinz-Siegfried}},
  issn         = {{1520-6106}},
  journal      = {{The Journal of Physical Chemistry B}},
  pages        = {{1384--1389}},
  title        = {{{Midinfrared Birefringence of Liquid Crystals, Polarimetry, and Intensity Modulators}}},
  doi          = {{10.1021/acs.jpcb.8b10039}},
  year         = {{2019}},
}

@article{35872,
  author       = {{Zhang, Bingru and Schmidtke, Jürgen and Kitzerow, Heinz-Siegfried}},
  issn         = {{2195-1071}},
  journal      = {{Advanced Optical Materials}},
  keywords     = {{Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials}},
  number       = {{8}},
  publisher    = {{Wiley}},
  title        = {{{Fabrication of Lyotropic Alignment Layers for Thermotropic Liquid Crystals Facilitated by a Polymer Template}}},
  doi          = {{10.1002/adom.201801766}},
  volume       = {{7}},
  year         = {{2019}},
}

@inproceedings{35870,
  author       = {{Temme, Julian and Meyers, Thorsten and Reker, Julia and Vidor, Fábio F. and Vollbrecht, Joachim and Kitzerow, Heinz-Siegfried and Paradies, Jan and Hilleringmann, Ulrich}},
  booktitle    = {{Fifth Conference on Sensors, MEMS, and Electro-Optic Systems}},
  editor       = {{du Plessis, Monuko}},
  publisher    = {{SPIE}},
  title        = {{{Improved organic thin-film transistor performance by dielectric layer patterning}}},
  doi          = {{10.1117/12.2500286}},
  year         = {{2019}},
}

@article{39971,
  author       = {{Kitzerow, Heinz-Siegfried}},
  issn         = {{1358-314X}},
  journal      = {{Liquid Crystals Today}},
  keywords     = {{Materials Chemistry, Inorganic Chemistry, Condensed Matter Physics}},
  number       = {{1}},
  pages        = {{23--30}},
  publisher    = {{Informa UK Limited}},
  title        = {{{Pawel Pieranski – crystallographer of liquids and Alfred-Saupe-prize laureate 2019}}},
  doi          = {{10.1080/1358314x.2019.1625161}},
  volume       = {{28}},
  year         = {{2019}},
}

@article{13343,
  author       = {{Vollbrecht, Joachim and Wiebeler, Christian and Bock, Harald and Schumacher, Stefan and Kitzerow, Heinz-Siegfried}},
  issn         = {{1932-7447}},
  journal      = {{The Journal of Physical Chemistry C}},
  number       = {{7}},
  pages        = {{4483--4492}},
  title        = {{{Curved Polar Dibenzocoronene Esters and Imides versus Their Planar Centrosymmetric Homologs: Photophysical and Optoelectronic Analysis}}},
  doi          = {{10.1021/acs.jpcc.8b10730}},
  volume       = {{123}},
  year         = {{2019}},
}

@article{8798,
  author       = {{Atorf, Bernhard and Friesen, Simon and Rennerich, Roman and Mühlenbernd, Holger and Zentgraf, Thomas and Kitzerow, Heinz-Siegfried}},
  issn         = {{1811-2382}},
  journal      = {{Polymer Science, Series C}},
  pages        = {{55--62}},
  title        = {{{Switchable Plasmonic Metasurface Utilizing the Electro-Optic Kerr Effect of a Blue Phase Liquid Crystal}}},
  doi          = {{10.1134/s1811238218010010}},
  volume       = {{60}},
  year         = {{2018}},
}

@article{1764,
  author       = {{Atorf, Bernhard and Rasouli, Hoda and Mühlenbernd, Holger and Reineke, Bernhard J. and Zentgraf, Thomas and Kitzerow, Heinz-Siegfried}},
  issn         = {{1932-7447}},
  journal      = {{The Journal of Physical Chemistry C}},
  number       = {{8}},
  pages        = {{4600--4606}},
  publisher    = {{American Chemical Society (ACS)}},
  title        = {{{Switchable Plasmonic Holograms Utilizing the Electro-Optic Effect of a Liquid-Crystal Circular Polarizer}}},
  doi          = {{10.1021/acs.jpcc.7b12609}},
  volume       = {{122}},
  year         = {{2018}},
}