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Martijn Kemerink - One of the best experts on this subject based on the ideXlab platform.

  • Ferroelectric Switching and electrochemistry of pyrrole substituted trialkylbenzene-1,3,5-tricarboxamides.
    Journal of polymer science. Part B Polymer physics, 2017
    Co-Authors: Xiao Meng, Andrey V. Gorbunov, René A. J. Janssen, Martijn Kemerink, W. S. Christian Roelofs, Stefan C. J. Meskers, Rint P. Sijbesma
    Abstract:

    We explore a new approach to organic Ferroelectric diodes using a benzene-tricarboxamide (BTA) core connected with C10 alkyl chains to pyrrole groups, which can be polymerized to provide a semiconducting Ferroelectric material. The compound possesses a columnar hexagonal liquid crystalline (LC) phase and exhibits Ferroelectric Switching. At low Switching frequencies, an additional process occurs, which leads to a high hysteretic charge density of up to ∼1000 mC/m2. Based on its slow rate, the formation of gas bubbles, and the emergence of characteristic polypyrrole absorption bands in the UV-Vis-NIR, the additional process is identified as the oxidative polymerization of pyrrole groups, enabled by the presence of amide groups. Polymerization of the pyrrole groups, which is essential to obtain semiconductivity, is limited to thin layers at the electrodes, amounting to ∼17 nm after cycling for 21 h. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 673-683.

  • True Ferroelectric Switching in thin films of trialkylbenzene-1,3,5-tricarboxamide (BTA)
    Physical chemistry chemical physics : PCCP, 2016
    Co-Authors: Andrey V. Gorbunov, Tristan Putzeys, I. Urbanavičiūtė, René A. J. Janssen, Michael Wübbenhorst, Rint P. Sijbesma, Martijn Kemerink
    Abstract:

    We have investigated the Ferroelectric polarization Switching properties of trialkylbenzene-1,3,5-tricarboxamide (BTA), which is a model system for a large class of novel organic Ferroelectric materials. In the solid state BTAs form a liquid crystalline columnar hexagonal phase that provides long range order that was previously shown to give rise to hysteretic dipolar Switching. In this work the nature of the polar Switching process is investigated by a combination of dielectric relaxation spectroscopy, depth-resolved pyroelectric response measurements, and classical frequency- and time-dependent electrical Switching. We show that BTAs, when brought in a homeotropically aligned hexagonal liquid crystalline phase, are truly Ferroelectric. Analysis of the transient Switching behavior suggests that the Ferroelectric Switching is limited by a highly dispersive nucleation process, giving rise to a wide distribution of Switching times.

Rint P. Sijbesma - One of the best experts on this subject based on the ideXlab platform.

  • Ferroelectric Switching and electrochemistry of pyrrole substituted trialkylbenzene-1,3,5-tricarboxamides.
    Journal of polymer science. Part B Polymer physics, 2017
    Co-Authors: Xiao Meng, Andrey V. Gorbunov, René A. J. Janssen, Martijn Kemerink, W. S. Christian Roelofs, Stefan C. J. Meskers, Rint P. Sijbesma
    Abstract:

    We explore a new approach to organic Ferroelectric diodes using a benzene-tricarboxamide (BTA) core connected with C10 alkyl chains to pyrrole groups, which can be polymerized to provide a semiconducting Ferroelectric material. The compound possesses a columnar hexagonal liquid crystalline (LC) phase and exhibits Ferroelectric Switching. At low Switching frequencies, an additional process occurs, which leads to a high hysteretic charge density of up to ∼1000 mC/m2. Based on its slow rate, the formation of gas bubbles, and the emergence of characteristic polypyrrole absorption bands in the UV-Vis-NIR, the additional process is identified as the oxidative polymerization of pyrrole groups, enabled by the presence of amide groups. Polymerization of the pyrrole groups, which is essential to obtain semiconductivity, is limited to thin layers at the electrodes, amounting to ∼17 nm after cycling for 21 h. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 673-683.

  • True Ferroelectric Switching in thin films of trialkylbenzene-1,3,5-tricarboxamide (BTA)
    Physical chemistry chemical physics : PCCP, 2016
    Co-Authors: Andrey V. Gorbunov, Tristan Putzeys, I. Urbanavičiūtė, René A. J. Janssen, Michael Wübbenhorst, Rint P. Sijbesma, Martijn Kemerink
    Abstract:

    We have investigated the Ferroelectric polarization Switching properties of trialkylbenzene-1,3,5-tricarboxamide (BTA), which is a model system for a large class of novel organic Ferroelectric materials. In the solid state BTAs form a liquid crystalline columnar hexagonal phase that provides long range order that was previously shown to give rise to hysteretic dipolar Switching. In this work the nature of the polar Switching process is investigated by a combination of dielectric relaxation spectroscopy, depth-resolved pyroelectric response measurements, and classical frequency- and time-dependent electrical Switching. We show that BTAs, when brought in a homeotropically aligned hexagonal liquid crystalline phase, are truly Ferroelectric. Analysis of the transient Switching behavior suggests that the Ferroelectric Switching is limited by a highly dispersive nucleation process, giving rise to a wide distribution of Switching times.

Andrey V. Gorbunov - One of the best experts on this subject based on the ideXlab platform.

  • Ferroelectric Switching and electrochemistry of pyrrole substituted trialkylbenzene-1,3,5-tricarboxamides.
    Journal of polymer science. Part B Polymer physics, 2017
    Co-Authors: Xiao Meng, Andrey V. Gorbunov, René A. J. Janssen, Martijn Kemerink, W. S. Christian Roelofs, Stefan C. J. Meskers, Rint P. Sijbesma
    Abstract:

    We explore a new approach to organic Ferroelectric diodes using a benzene-tricarboxamide (BTA) core connected with C10 alkyl chains to pyrrole groups, which can be polymerized to provide a semiconducting Ferroelectric material. The compound possesses a columnar hexagonal liquid crystalline (LC) phase and exhibits Ferroelectric Switching. At low Switching frequencies, an additional process occurs, which leads to a high hysteretic charge density of up to ∼1000 mC/m2. Based on its slow rate, the formation of gas bubbles, and the emergence of characteristic polypyrrole absorption bands in the UV-Vis-NIR, the additional process is identified as the oxidative polymerization of pyrrole groups, enabled by the presence of amide groups. Polymerization of the pyrrole groups, which is essential to obtain semiconductivity, is limited to thin layers at the electrodes, amounting to ∼17 nm after cycling for 21 h. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 673-683.

  • True Ferroelectric Switching in thin films of trialkylbenzene-1,3,5-tricarboxamide (BTA)
    Physical chemistry chemical physics : PCCP, 2016
    Co-Authors: Andrey V. Gorbunov, Tristan Putzeys, I. Urbanavičiūtė, René A. J. Janssen, Michael Wübbenhorst, Rint P. Sijbesma, Martijn Kemerink
    Abstract:

    We have investigated the Ferroelectric polarization Switching properties of trialkylbenzene-1,3,5-tricarboxamide (BTA), which is a model system for a large class of novel organic Ferroelectric materials. In the solid state BTAs form a liquid crystalline columnar hexagonal phase that provides long range order that was previously shown to give rise to hysteretic dipolar Switching. In this work the nature of the polar Switching process is investigated by a combination of dielectric relaxation spectroscopy, depth-resolved pyroelectric response measurements, and classical frequency- and time-dependent electrical Switching. We show that BTAs, when brought in a homeotropically aligned hexagonal liquid crystalline phase, are truly Ferroelectric. Analysis of the transient Switching behavior suggests that the Ferroelectric Switching is limited by a highly dispersive nucleation process, giving rise to a wide distribution of Switching times.

René A. J. Janssen - One of the best experts on this subject based on the ideXlab platform.

  • Ferroelectric Switching and electrochemistry of pyrrole substituted trialkylbenzene-1,3,5-tricarboxamides.
    Journal of polymer science. Part B Polymer physics, 2017
    Co-Authors: Xiao Meng, Andrey V. Gorbunov, René A. J. Janssen, Martijn Kemerink, W. S. Christian Roelofs, Stefan C. J. Meskers, Rint P. Sijbesma
    Abstract:

    We explore a new approach to organic Ferroelectric diodes using a benzene-tricarboxamide (BTA) core connected with C10 alkyl chains to pyrrole groups, which can be polymerized to provide a semiconducting Ferroelectric material. The compound possesses a columnar hexagonal liquid crystalline (LC) phase and exhibits Ferroelectric Switching. At low Switching frequencies, an additional process occurs, which leads to a high hysteretic charge density of up to ∼1000 mC/m2. Based on its slow rate, the formation of gas bubbles, and the emergence of characteristic polypyrrole absorption bands in the UV-Vis-NIR, the additional process is identified as the oxidative polymerization of pyrrole groups, enabled by the presence of amide groups. Polymerization of the pyrrole groups, which is essential to obtain semiconductivity, is limited to thin layers at the electrodes, amounting to ∼17 nm after cycling for 21 h. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 673-683.

  • True Ferroelectric Switching in thin films of trialkylbenzene-1,3,5-tricarboxamide (BTA)
    Physical chemistry chemical physics : PCCP, 2016
    Co-Authors: Andrey V. Gorbunov, Tristan Putzeys, I. Urbanavičiūtė, René A. J. Janssen, Michael Wübbenhorst, Rint P. Sijbesma, Martijn Kemerink
    Abstract:

    We have investigated the Ferroelectric polarization Switching properties of trialkylbenzene-1,3,5-tricarboxamide (BTA), which is a model system for a large class of novel organic Ferroelectric materials. In the solid state BTAs form a liquid crystalline columnar hexagonal phase that provides long range order that was previously shown to give rise to hysteretic dipolar Switching. In this work the nature of the polar Switching process is investigated by a combination of dielectric relaxation spectroscopy, depth-resolved pyroelectric response measurements, and classical frequency- and time-dependent electrical Switching. We show that BTAs, when brought in a homeotropically aligned hexagonal liquid crystalline phase, are truly Ferroelectric. Analysis of the transient Switching behavior suggests that the Ferroelectric Switching is limited by a highly dispersive nucleation process, giving rise to a wide distribution of Switching times.

S. G. Yudin - One of the best experts on this subject based on the ideXlab platform.

  • Field amplification and Ferroelectric Switching in a bilayer linear insulator-Ferroelectric heterostructure
    Physics of the Solid State, 2009
    Co-Authors: V. V. Lazarev, S. P. Palto, L. M. Blinov, S. G. Yudin
    Abstract:

    Langmuir-Blodgett thin-film heterostructures consisting of molecular layers of the Ferroelectric copolymer poly(vinylidene fluoride-trifluoroethylene) and an insulator (the azo dye) are prepared and studied. A physical model is proposed for amplification of a local electric field in regions of arrangement of the dye and Ferroelectric molecules. Experimental studies of the Ferroelectric Switching confirm that, in the heterostructures, the effective external coercive voltage decreases and the switched polarization increases.

  • AntiFerroelectric and Ferroelectric Switching of a liquid crystal in Langmuir-Blodgett films under strong confinement conditions
    Crystallography Reports, 2006
    Co-Authors: Lev M. Blinov, S. P. Palto, Vladimir V. Lazarev, A. R. Geivandov, S. G. Yudin
    Abstract:

    An antiFerroelectric liquid-crystal (LC) material formed of banana-shaped molecules in the sandwich metal-thin Langmuir-Blodgett film-metal geometry, which is typical of solid-state technology, is investigated. Upon heating the thin-film elements, the material passes to the high-temperature (68–127°C) LC B 2 phase, which, despite severe limitation on the film thickness (∼100 nm or less), exhibits antiFerroelectric Switching, which was previously observed only in bulk samples (10 μm thick) of the LC studied. At film thicknesses smaller than ∼40 nm, Ferroelectric Switching is observed, which is caused by the stabilization of the Ferroelectric LC phase by the boundary surfaces. The largest values of the switched polarization of films (∼400 nC/cm2) are comparable with the polarization of bulk samples. The coercive field increases with decreasing film thickness and reaches ∼106 V/cm for the thinnest films. This value corresponds to the intrinsic coercive field of the Ferroelectric under conditions of a strong surface effect, which suppresses domain processes.

  • kinetics of Ferroelectric Switching in ultrathin films
    Physical Review B, 2003
    Co-Authors: G. Vizdrik, Stephen Ducharme, V M Fridkin, S. G. Yudin
    Abstract:

    The kinetics of polarization Switching in ultrathin Ferroelectric polymer films exhibit a critical behavior; there is a pronounced slowing just above the coercive field and just below the critical temperature. The critical slowing is observed in the Switching kinetics of Ferroelectric Langmuir-Blodgett films of 70% vinylidene-fluoride and 30% trifluoroethylene copolymer with thickness up to 30 ML. Thicker films exhibit an exponential dependence on the field and temperature that is normally associated with extrinsic Switching by domain nucleation and growth. We show that the critical behavior arises naturally from the dynamics of homogeneous intrinsic Switching in the context of mean-field theory. These results have important implications for the modeling and control of the Ferroelectric films in nonvolatile computer memories and solid-state data storage media.

  • Ferroelectric Switching of Combined Ultrathin Langmuir-Blodgett Films
    Ferroelectrics, 2003
    Co-Authors: Vladimir M. Fridkin, G. Vizdrik, S. G. Yudin
    Abstract:

    The possibility of Ferroelectric Switching in one monolayer of Langmuir-Blodgett film is demonstrated. The sample studied consisted of separate Ferroelectric copolymer with nonFerroelectric antrakhinon.

  • Novel Switching phenomena in Ferroelectric Langmuir-Blodgett films
    Applied Physics Letters, 1995
    Co-Authors: A. V. Bune, Vladimir M. Fridkin, S. P. Palto, Lev M. Blinov, Stephen Ducharme, N. Petukhova, S. G. Yudin
    Abstract:

    We have established Ferroelectric Switching and observed a novel conductance Switching phenomenon in Ferroelectric polymer films fabricated by the Langmuir–Blodgett technique. The films consist of 10–30 monolayers (ML) of a copolymer of vinylidene fluoride (70%) and trifluoroethylene (30%), exhibiting a first‐order Ferroelectric phase transition at 70 °C and nearly rectangular Ferroelectric and conductance hysteresis at 24 °C. Ferroelectric Switching is accompanied by Switching of the conductance by three orders of magnitude. A model describing this Switching phenomenon is proposed.