logo logo logo

Department of Dielectrics

Institute of Physics of the Czech Academy of Sciences


group Dielectric and IR spectroscopy science Dielectric and IR spectroscopy group THz and pump-probe science THz science and technology group Photon and neutron scattering group Light and neutron scattering group Theory Theory and
simulations
group Solid materials science Solid-state materials science group Liquid crystal material science Liquid crystals

About us

Main activities of Department of Dielectrics cover experimental and theoretical investigations of high-permittivity insulators like liquid crystals, ferroelectrics, multiferroics, piezoelectrics, semiconductor nanostructures, and low-loss materials.

fzu
Photo of people of Dielectrics
Our mission: Understanding the materials for which the frequency dependence of dielectric function can be probed by capacitance, waveguide or optical techniques. Experimental research in the Department of Dielectrics is mostly based on dielectric, infrared, time-domain THz, Raman and neutron spectroscopy, but also calorimetry, nonlinear optics and scanning probe microscopy measurements. The information on the core research activities organized within our six principal research groups can be accessed through the following links:

The most significant fresh scientific results of our deparment are listed in the section Highlights.

Oncoming seminars & workshops

Seminars to be announced.

News & Public

fzu fig
05.11.2024 Research

Dipolar liquid in the solid phase

Researchers from the Department of Dielectrics together with their colleagues from the Faculty of Mathematics and Physics of Charles University have succeeded for the first time in observing an electrical analogue of the spin liquid in EuAl12O19 [Adv. Mater. 36, 2410282 (2024)].

(show more)

fig fig
02.10.2024 Research

Competing synclinic and anticlinic interactions in smectic phases of bent-core mesogens

In collaboration with University of Chemistry and Technology, Prague, and Warsaw University, Vladimíra Novotná and Natalia Podoliak studied new sophisticated molecular systems, which form structurally complex synclinic and anticlinic phases [J. Mater. Chem. C 12,10903 (2024)]. The texture observed in the polarized light microscope and the molecular structure is highlighted in the inside back cover of the 29th issue of Journal of Materials Chemistry C.

(show more)

fzu fig
30.09.2024 Media

Researchers’ Night at the Liquid Crystals lab

Natalia Podoliak and Petr Ondrejkovič participated in the Researchers’ Night with an educational excursion called "Fairy tale about a little Liquid Crystal" aimed for children aged 6-12. A short announcement about this activity was broadcasted by the Czech TV in the main TV news (27.9.2024) and the news program about science named "Věda 24" (29.9.2024).

(show more)

fzu fig
08.03.2024 Exhibition

Vladimíra Novotná - The beauty of liquid crystals

The exhibition is hosted by The small gallery of scientific images at the Faculty of Mathematics and Physics, Charles University, Prague (Ke Karlovu 3, 1st floor). and will last from 5.3. to 6.5.2024. The opening takes place on March 11, 2024 from 5:00 p.m.

(show more)

fig fig
20.10.2023 Award

Anna Radochová won the Czech Head Award 2023 (České hlavičky) for secondary school students

Anna Radochová received this prestigious award in the category UNIVERSUM for her successful project "Properties of new photosensitive liquid crystals" under supervision of Alexej Bubnov. The ceremony will be broadcasted by the Czech Television on the 18th of November 2023.

(show more)

fig fig
05.07.2023 Research

Charged domain walls in BaTiO3 crystals emerging from superdomain boundaries

Petr Bednyakov and Jirka Hlinka observed a transient domain structure with multiple superdomains whose boundaries transform into charged domain walls in BaTiO3 [Adv. Electron. Mater. 9, 2300005 (2023)]. These superdomains highlighted the inside front cover of the June issue of Advanced Electronic Materials.

(show more)


Latest Highlights
fzu fig

Antiskyrmions in ferroelectric barium titanate

Our recent molecular dynamics computational study reveals that the bulk crystal of the archetypal ferroelectric perovskite BaTiO3 can host ferroelectric antiskyrmions at zero field. We show that the antiskyrmion has just 2-3 nm in diameter and that it carries a very exotic topological charge of minus two [Phys. Rev. Lett. 133, 066802 (2024)].

(show more)
fzu fig

Coexisting polarization mechanisms in tetragonal tungsten bronze Ca0.3Ba0.7Nb2O6

We have proven that Ca0.3Ba0.7Nb2O6 displays a ferroelectric phase transition of mixed displacive and order-disorder character, and that its paraelectric phase does not show traces of relaxor behaviour but precursor effects as polar fluctuations below about 550 K [Phys. Rev. B 110, 104302 (2024)].

(show more)
fzu fig

Ultrafast long-distance expansion of electron-hole plasma in direct bandgap semiconductors

Transport of charge carriers inside crystals is determined by their energy band structure which only permits velocities smaller than ~c/100 in known materials. We demonstrated that ultrafast and long-distance propagation of electron-hole plasma (velocities up to c/10, reaching more than 100 μm) is possible as a quite general result of fundamental electron-photon interaction in direct bandgap semiconductors upon strong pulse photoexcitation with low photon excess energy above the bandgap [PRL 130, 226301 (2023) & Nanophotonics 13, 1859 (2024)].

(show more)
fzu fig

Paving the way to a 3-state thermal switch using antiferroelectric Pb(Zr1-xTix)O3

We propose a novel approach of phase-control in Pb(Zr0.95Ti0.05)O3 (PZT95/5) based on the thermal behavior of its phases. Our results show the possibility to thermally switch among three states near room temperature using small temperature gradients by heating-cooling cycles at slow rates. Thus, PZT95/5 ceramics are potential materials for room temperature device applications [Acta Materialia, 119208 (2023), online].

(show more)
fzu fig

Zigzag charged domain walls in ferroelectric PbTiO3

We report a theoretical investigation of a charged 180-degree domain wall in ferroelectric PbTiO3, compensated by randomly distributed immobile charge defects. We predict that domain walls form a zigzag pattern and we discuss their properties in a broad interval of compensation-region widths. The zigzag is accompanied by a local polarization rotation which we explain to provide an efficient mechanism for charge compensation [Phys. Rev. B 107, 094102 (2023)].

(show more)

Latest Key Articles

figfig
A. Chaudron, Z. Li, A. Finco, P. Marton, P. Dufour, A. Abdelsamie, J.Fischer, S. Collin, B. Dkhil, J. Hlinka, V. Jacques , J.-Y. Chauleau, M. Viret, K. Bouzehouane, S. Fusil, and V. Garcia

Electric-field-induced multiferroic topological solitons

Nat. Mater. (2024).
figfig
G. Bastien, D. Repček, A. Eliáš, A. Kancko, Q. Courtade, T. Haidamak, M. Savinov, V. Bovtun, M. Kempa, K. Carva, M. Vališka, P. Doležal, M. Kratochvílová, S. A. Barnett, P. Proschek, J. Prokleška, C. Kadlec, P. Kužel, R. H. Colman, and S. Kamba

A frustrated antipolar phase nalogous to classical spin liquids

Adv. Mater. 36, 2410282 (2024).
figfig
E. Zatterin, P. Ondrejkovic, L. Bastogne, C Lichtensteiger, L Tovaglieri, D.A. Chaney, A. Sasani, T. Schülli, A. Bosak, S. Leake, P. Zubko, P. Ghosez, J. Hlinka, J.-M. Triscone, and M. Hadjimichael

Assessing the ubiquity of Bloch domain walls in ferroelectric lead litanate superlattices

Phys. Rev. X 14, 041052 (2024).
figfig
K. Tesař, J. Luňáčková, M. Jex, M. Žaloudková, R. Vrbová, M. Bartoš, P. Klein, L. Vištejnová, J. Dušková, E. Filová, Z. Sucharda, M. Steinerová, S. Habr, K. Balík, and A. Singh

In vivo and in vitro study of resorbable magnesium wires for medical implants: Mg purity, surface quality, Zn alloying and polymer coating

J. Magnes. Alloy 12(6), 2472 (2024).
figfig
T. Troha, F. Klimovič, T. Ostatnický, H. Němec, and P. Kužel

Photon-assisted ultrafast electron-hole plasma expansion in direct band semiconductors

Nanophotonics 13, 1859 (2024).
figfig
M. A. P. Gonçalves, M. Paściak, and J. Hlinka

Antiskyrmions in ferroelectric barium titanate

Phys. Rev. Lett. 133, 066802 (2024).
figfig
M. Mrukiewicz, M. Czerwinski, N. Podoliak, D. Repček, P. Perkowski, R. J. Mandle, and D. Weglowska

Polar nematic phases with enantiotropic ferro- and antiferroelectric behaviour

J. Mater. Chem. C 12, 7214 (2024).
figfig
J. Svoboda, V. Kozmík, K. Bajzíková, M. Kohout, V. Novotná, N. Podoliak, D. Pociecha, and E. Gorecka

Competing synclinic and anticlinic interactions in smectic phases of bent-core mesogens.

J. Mater. Chem. C 12, 10903 (2024).
figfig
V. Novotná, L. Lejček, and N. Podoliak

Twisted domains in ferroelectric nematic liquid crystals

J. Mol. Liq. 403, 124873 (2024).
figfig
P. Kumar, M. Šilhavík, M. R. Parida, P. Kužel, and J. Červenka

3D graphene straintronics for broadband terahertz modulation

Adv. Electron. Mater., 2300853 (2024).

Last update: November 27, 2024 (admin)