Achtung:

Sie haben Javascript deaktiviert!
Sie haben versucht eine Funktion zu nutzen, die nur mit Javascript möglich ist. Um sämtliche Funktionalitäten unserer Internetseite zu nutzen, aktivieren Sie bitte Javascript in Ihrem Browser.

Department Chemie
Physical chemistry of polymer enhanced materials for advanced electro-optics
Dr. rer. nat. Alexander Lorenz
Bildinformationen anzeigen

Publikationen

Publications in peer reviewed journals

19. A. Lorenz, F. Omairat, L. Braun, V. Kolosova, Nematic copolymer network LCs for swift continuous phase modulation and opaque scattering states, Mol. Cryst. and Liq. Cryst. 646, 220 (2016). http://dx.doi.org/10.1080/15421406.2017.1288001

18. A. Lorenz, L. Braun, V. Kolosova, Continuous Optical Phase Modulation in a Copolymer Network Nematic Liquid Crystal, ACS Photonics 3, 1188 (2016). http://pubs.acs.org/doi/abs/10.1021/acsphotonics.6b00072

17.  L. Braun, A. Lorenz, V. Kolosova, R. Hyman, T. D. Wilkinson, Continuous phase modulation in polymer-stabilized liquid crystals, Emerging Liquid Crystal Technologies XI, edited by Liang-Chy Chien, Proceedings of SPIE Vol. 9769 (SPIE, Bellingham, WA, 2016). http://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.2222379

16.  R. M. Hyman, A. Lorenz, T. D. Wilkinson, Phase modulation using different orientations of a chiral nematic in liquid crystal over silicon devices, Liquid Crystals 43, 83 (2016). http://dx.doi.org/10.1080/02678292.2015.1061146

15.  J. Yuan, G. Tan, D. Xu, F. Peng, A. Lorenz, S.-T. Wu, A low-voltage and fast-response polymer-stabilized hyper-twisted nematic liquid crystal, Optical Materials Express 5, 1341 (2015). http://dx.doi.org/10.1364/OME.5.001339 

14.  R. M. Hyman, A. Lorenz, S. M. Morris, T. D. Wilkinson, Polarization-independent phase modulation using a blue-phase liquid crystal over silicon device, Applied Optics 53, 6925 (2014). http://www.opticsinfobase.org/abstract.cfm?URI=ao-53-29-6925

13.  D. M. Agra-Kooijman, G. Singh, A. Lorenz, P. J. Collings, H.-S. Kitzerow, S. Kumar, Columnar Molecular Aggregation in the Aqueous Solutions of Disodium Cromoglycate, Phys. Rev. E 89, 062504 (2014). http://dx.doi.org/10.1103/PhysRevE.89.062504

12.  A. Lorenz, D. J. Gardiner, S. M. Morris, F. Castles, M. M. Qasim, S. S. Choi, W.-S. Kim, H. J. Coles, T. D. Wilkinson, Electrical addressing of polymer stabilized hyper-twisted chiral nematic liquid crystals with interdigitated electrodes: Experiment and model, Appl. Phys. Lett. 104, 071102 (2014). http://dx.doi.org/10.1063/1.4865558

11.  A. Lorenz, N. Zimmermann, S. Kumar, D. R. Evans, G. Cook H.-S. Kitzerow, Bilayers in Nanoparticle-Doped Polar Mesogens, Phys. Rev. E 88, 062505 (2013). http://dx.doi.org/10.1103/PhysRevE.88.062505

10.  G. Nordendorf, A. Lorenz, A. Hoischen, J. Schmidtke, H. Kitzerow, D. Wilkes M. Wittek, Hysteresis and memory factor of the Kerr effect in blue phases, J. Appl. Phys. 114, 173104 (2013). http://dx.doi.org/10.1063/1.4828477

9.    Front page: D.-H. Ko, S. M. Morris, A. Lorenz, F. Castles, H. Butt, D. J. Gardiner, M. M. Qasim, B. Wallikewitz, P. J. W. Hands, T. D. Wilkinson, G. Amaratunga, H. J. Coles R. H. Friend, A nano-patterned photonic crystal laser with a dye-doped liquid crystal, Appl. Phys. Lett. 103, 051101 (2013). http://dx.doi.org/10.1063/1.4816243

8.    Feature: A. Lorenz, N. Zimmermann, S. Kumar, D. R. Evans, G. Cook H.-S. Kitzerow, X-ray scattering of nematic liquid crystal nano-dispersion with negative dielectric anisotropy, Appl. Opt. 52, E1-E5 (2013). http://dx.doi.org/10.1364/AO.52.0000E1

7.    A. Lorenz, N. Zimmermann, S. Kumar, D. R. Evans, G. Cook, M. Fernández Martínez H.-S. Kitzerow, Doping a Mixture of Two Smectogenic Liquid Crystals with Barium Titanate Nanoparticles, J. Phys. Chem. B 117, 937−941 (2013). http://dx.doi.org/10.1021/jp310624c

6.    A. Lorenz, N. Zimmermann, S. Kumar, D. R. Evans, G. Cook H.-S. Kitzerow, Doping the liquid crystal 5CB with milled BaTiO3 nanoparticles, Phys. Rev. E. 86, 051704 (2012). http://dx.doi.org/10.1103/PhysRevE.86.051704

5.    A. Lorenz, H.-S. Kitzerow, Efficient electro-optic switching in a photonic liquid crystal fiber, Appl. Phys. Lett. 98, 241106 (2011). http://dx.doi.org/10.1063/1.3599848

4.    A. Lorenz, R. Schuhmann, H.-S. Kitzerow, Switchable waveguiding in two liquid crystal-filled photonic crystal fibers, Appl. Opt. 49, 3846–3853 (2010). http://dx.doi.org/10.1364/AO.49.003846

3.    A. Lorenz, R. Schuhmann, H.-S. Kitzerow, Infiltrated photonic crystal fiber: experiments and liquid crystal scattering model, Opt. Express 18, 3519‐3530 (2010). http://dx.doi.org/10.1364/OE.18.003519

2.    A. Lorenz, H.-S. Kitzerow, A. Schwuchow, J. Kobelke, H. Bartelt, Photonic crystal fiber with a dual-frequency addressable liquid crystal: behavior in the visible wavelength range, Opt. Express 16, 19375‐19381 (2008). http://dx.doi.org/10.1364/OE.16.019375

1.    H.-S. Kitzerow, A. Lorenz, H. Matthias, Tuneable photonic crystals obtained by liquid crystal infiltration, physica status solidi (a) 11 (204), 3754-3767 (2007). http://dx.doi.org/10.1002/pssa.200776404 

Oral Presentations

29.  A. Lorenz, D. R. Evans, Photovoltaic LC test cells driven by focused CW laser light, International Liquid Crystal Conference 2016, Kent, OH, USA (July 31 – August 5, 2016).

28.  A. Lorenz, L. Braun, V. Kolosova, Polymer enhanced LCs with continuous optical phase modulation, Joint Conference of the British and German Liquid Crystal Societies Edinburgh, UK (March 21 – 23, 2016).

27.  INVITED: A. Lorenz, Liquid crystals for photonics: Properties, applications, challenges, Europhotonics Spring School 2016, Il de Porquerolles, France (March 29 – April 1, 2016).

26.  INVITED: A. Lorenz, L. Braun, V. Kolosova, R. M. Hyman, T. D. Wilkinson, Continuous phase modulation in polymer-stabilized liquid crystals, SPIE. Photonics West – Opto 2016: Emerging Liquid Crystal Technologies, San Francisco, CA, USA (February 16 – 17, 2016).

25.  INVITED: A. Lorenz, Polymer-enhanced electro-optics in various types of LCs, EMN Meeting on Liquid Crystal, Orlando, FL, USA (February 16 – 19, 2016).

24.  A. Lorenz, Continuous electro-optical phase modulation in liquid crystals with added polymer, 13. Convention of the Graduate Program DFG RTG-1464, Paderborn, Germany (November 24 – 25, 2015).

23.  A. Lorenz, Continuous electro-optical phase modulation in liquid crystal polymer composites, NMWP JungakademikerInnen-Symposium: Materialien für die Photonik, Universität Duisburg-Essen, Essen, Germany (September 30, 2015).

22.  INVITED: A. Lorenz, Electro-optics and dielectric measurements in polymer-stabilized liquid crystals of high chirality, IMID 2015: The 15th International Meeting on Information Display, Daegu, Republic of Korea (August 18 – 21, 2015).

21.  A. Lorenz, D. J. Gardiner, R. Hyman, S. M. Morris, T. D. Wilkinson, Electro-optics in fast switching, polymer-stabilized liquid crystals of high chirality, DPG-Frühjahrstagung 2015, Berlin, Germany (March 15 – 20, 2015).

20.  A. Lorenz, R. Hyman, S. M. Morris, T. D. Wilkinson, Induced blue phase in E7: Polymer-stabilization and phase modulation properties, 42nd German Liquid Crystal Conference, Stuttgart, Germany (March 4 – 6, 2015).

19.  INVITED: A. Lorenz, D. J. Gardiner, R. Hyman, T. D. Wilkinson, Polymer-stabilized N* and blue phase liquid crystals: Driving light valves and optical phase modulators, EMN Meeting on Polymer, Orlando, FL, USA (January 7 – 10, 2015).

18.  A. Lorenz, D. J. Gardiner, S. M. Morris, T. D. Wilkinson, Polymer-Stabilized Liquid Crystal Light Modulators with Micopatterned Electrodes, Polydays 2014, Berlin, Germany (September 30 – October 2, 2014).

17.  A. Lorenz, D. M. Agra-Kooijman, N. Zimmermann, H.-S. Kitzerow, D. R. Evans, S. Kumar, Bilayer gelation in nanoparticle-doped nCB-homologues, International Liquid Crystal Conference 2014, Dublin, Ireland (June 29 – July 4, 2014).

16.  S. Morris, D.-H. Ko, A. Lorenz, F. Castles, M. Quasim, D. Gardiner, P. Hands, T. Wilkinson, H. Coles, R. Friend, Nano-patterned photonic crystal lasers with tuneable liquid crystal layers, International Liquid Crystal Conference 2014, Dublin, Ireland (June 29 – July 4, 2014).

15.  A. Lorenz, D. J. Gardiner, S. M. Morris, F. Castles, M. M. Qasim, S. S. Choi, W.-S. Kim, H. J. Coles, T. D. Wilkinson, Electrical addressing of polymer stabilized hyper-twisted chiral nematic liquid crystals with interdigitated electrodes: Experiment and model, 41st Topical Meeting on Liquid Crystals 2014, Magdeburg, Germany (March 25 – 27, 2014).

14.  A. Lorenz, N. Zimmermann, S. Kumar, D. R. Evans H.-S. Kitzerow, Nanoparticle induced smectic phase with unusual layer spacing in 4-cyano-4'-pentylbiphenyl and several homologues, 46th Biennial Meeting of the German Colloid Society, Paderborn, Germany (September 23 – 25, 2013).

13.  INVITED: A. Lorenz, X-ray Diffraction: From Fundamentals to Uses in Liquid Crystal Research, I-CAMP•13 Summer School on Liquid Crystals, Cambridge, UK (June 26 – July 6, 2013).

12.  A. Lorenz, N. Zimmermann, S. Kumar, D. R. Evans, G. Cook H.-S. Kitzerow, Liquid crystal multilayers adsorbed on nanoparticles with unusual layer spacing in 5CB, British Liquid Crystal Society Annual Meeting, Cambridge, UK (March 25 – 27, 2013).

11.  INVITED: A. Lorenz and H.-S. Kitzerow, Switchable Waveguiding in Photonic Liquid Crystal Microstructures – Glenn Brown Prize Lecture, International Liquid Crystal Conference 2012, Mainz, Germany (August 19 – 24, 2012).

10.  G. Nordendorf, A. Lorenz, A. Hoischen, J. Schmidtke, H. Kitzerow, D. Wilkes, M. Wittek, Hysteresis of the Kerr effect in blue phases, International Liquid Crystal Conference 2012, Mainz, Germany (August 19 – 24, 2012).

9.    H.-S. Kitzerow, A. Lorenz, C. Meier, Liquid crystals and organic / inorganic hybrid systems for functionalized optoelectronic and photonic devices, 1st Europhotonics Spring School, Barcelona, Spain (March 25 – 31, 2012).

8.    A. Lorenz, H.-S. Kitzerow, Polarizing Effects in Switchable Photonic Crystal Fibers, International liquid crystal conference 2010, Krakow, Poland (July 11 – July 16, 2010).

7.    A. Lorenz, R. Schuhmann, H.-S. Kitzerow, Switchable waveguiding in liquid crystal filled photonic crystal fibers, Convention of the DFG Graduate Program 1464, Paderborn, Germany (Mai 27 – 28, 2010).

6.    A. Lorenz, R. Schuhmann, H.-S. Kitzerow, Liquid crystal infiltrated photonic crystal fibers, DPG Frühjahrstagung der Sektion Kondensierte Materie (SKM), Regensburg, Germany (March 21 – 26, 2010).

5.    A. Lorenz, R. Schuhmann, H.-S. Kitzerow, Waveguiding in infiltrated photonic crystal fibers: experiments and liquid crystal scattering model, 38th Topical Meeting on Liquid Crystals, Mainz, Germany (March 10 – 12, 2010).

4.    A. Lorenz, R. Schuhmann, H.-S. Kitzerow, Scattering in liquid crystals and the useful application in switchable waveguides, Convention of DFG Graduate Program 1464, Bad Karlshafen, Germany (November 26 – 27, 2009).

3.    A. Lorenz, H.-S. Kitzerow, Switchable waveguides based on optically anisotropic photonic band gap structures for visible and near infrared light, Convention of DFG Graduate Program 1464, Gehrden, Germany (May, 7 – 8, 2009).

2.    A. Lorenz, H.-S. Kitzerow, Photonic Crystal Fibers filled with Liquid Crystals - Switchable Waveguides in the Visible and Infrared Spectral Region, JCF-Spring symposium (Frühjahrssymposium),Essen, Germany (March, 11 – 14, 2009).

1.    A. Lorenz, H.-S. Kitzerow, A. Schwuchow, J. Kobelke, H. Bartelt, Photonic crystal fibers filled with Liquid Crystals, International Liquid Crystal Conference 2008, Jeju Island, Republic of Korea (June 29 – July 4, 2008).

Poster Presentations

A. Lorenz, L. Braun, V. Kolosova, "Nematic copolymer network LCs for swift continuous phase modulation," International Liquid Crystal Conference 2016, Kent, OH, USA, (July 31 – August 5, 2016).

L. Braun, A. Lorenz, "Surface grafted crosslinker in polymer network liquid crystals," Joint Conference of the British and German Liquid Crystal Societies Edinburgh, UK (March 21 – 23, 2016).

A. Lorenz, Dean R. Evans, "Photovoltaic responses of purpose designed liquid crystal test cells," Manfred Eigen Nachwuchswissenschaftlergespräche, Max-Planck-Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany, (April 6 – 8, 2016).

A. Lorenz, "Electro-optics in polymer network LC composites – preliminary studies in transparent test cells," Liquid Crystals Gordon Research Conference 2015: Liquid Crystallinity in Soft Matter at and Beyond Equilibrium, Biddeford (ME), USA, (June 21 – 26, 2015).

A. Lorenz, D. M. Agra-Kooijman, D. R. Evans, H.-S. Kitzerow, S. Kumar, "A soft, bilayer phase in nanoparticle-doped n-CB homologues," DPG-Frühjahrstagung 2015, Berlin, Germany, (March 15 – 20, 2015).

R. Hyman, A. Lorenz, S. Morris, T. Wilkinson, "Phase Modulation of Light using a Polymer Stabilised Blue Phase Liquid Crystal," International Liquid Crystal Conference 2014, (Dublin Ireland, June 29 – July 4, 2014).

A. Lorenz, N. Zimmermann, S. Kumar, D. R. Evans, G. Cook, and H.-S. Kitzerow, "Multilayers with unusual layer spacing in nanoparticle doped 5CB," 40th Topical Meeting on Liquid Crystals 2013, Paderborn (March 20 – 22, 2013).

A. Lorenz, N. Zimmermann, S. Kumar, D. R. Evans, G. Cook, M. Fernández Martínez, N. Theyencheri, and H.-S. Kitzerow, "Doping an eutectic mixture of 8CB and 8OCB with harvested ferroelectric nanoparticles," International Liquid Crystal Conference 2012, Mainz, (August 19 – 24, 2012).

A. Lorenz, H.-S. Kitzerow, "Electro-optic modulators with liquid crystal-filled micro-channels," Frontier of Soft Matter 2012, Boulder CO, USA (May 16 – 18, 2012).

 

M. Urbanski, M. Wahle, A. Lorenz, C. Meier, H.-S. Kitzerow, "Tunable Photonic Structures using Liquid Crystals," 1st Europhotonics Spring School, Barcelona, Spain (March 25 – 31, 2012). 

 

A. Lorenz, H.-S. Kitzerow, M. A. Schmidt, H. Tyagi, N. Joly,M. Scharrrer, S. Rammler and P. St. J. Russell,"Step-Index Silica Fiber with Parallel Liquid-Crystal-Filled Micro-Channel" 38th Topical Meeting on Liquid Crystals (German Liquid Crystal Conference 2011), Hamburg (March 30 – April 1 2010).

 

A. Lorenz, R. Schuhmann, H.-S. Kitzerow, "Modal Dispersion of Waveguides with Escaped Radial Director Fields: ARROW-Study Of Tunable Photonic Crystal Fibers," 37th Topical Meeting on Liquid Crystals, Stuttgart (April 1 – 3, 2009).

 

A. Lorenz, H.-S. Kitzerow, A. Schwuchow, J. Kobelke, H. Bartelt, "Photonic Crystal Fiber with Dual Frequency Response," 37th Topical Meeting on Liquid Crystals, Stuttgart (April 1 – 3, 2009).

 

A. Lorenz, H.-S. Kitzerow, A. Schwuchow, J. Kobelke, H. Bartelt, "Photonic crystal fibers filled with liquid crystals - fibers with active cladding," KSOP Summer School, Bad Herrenalb (August 20 – 21, 2008).

 

A. Lorenz, H.-S. Kitzerow, A. Schwuchow, J. Kobelke, H. Bartelt, "Photonic crystal fibers filled with liquid crystals - fibers with active cladding," International Liquid Crystal Conference 2008, Jeju Island Korea (June 29 – July 4, 2008).

 

A. Lorenz, H.-S. Kitzerow, "Photonic crystal fibers filled with liquid crystals - band gap fibers with active cladding," 36th Topical Meeting on Liquid Crystals, Magdeburg (March 12 – 14, 2008).

Gruppenleitung

Dr. Alexander Lorenz

Physikalische Chemie

Nachwuchsgruppenleiter, DFG Projekt Photoaktive Flüssigkristall Nanodispersionen

Alexander Lorenz
Telefon:
+49 5251 60-5728
Fax:
+49 5251 60-4208
Büro:
NW 1 872

Die Universität der Informationsgesellschaft