scholarly journals Freedericksz Transitions in Twisted Ferronematics Subjected to Magnetic and Laser Field

Crystals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 567
Author(s):  
Cristina Cirtoaje ◽  
Gabriela Iacobescu ◽  
Emil Petrescu
Keyword(s):  
Liquid Crystals ◽  
Critical Field ◽  
Laser Field ◽  
Laser Intensity ◽  
Continuum Theory ◽  
Laser Fields ◽  
Elastic Continuum ◽  
Saturation Field ◽  
Anchoring Strength ◽  
Cell Support

The influence of the anchoring forces on the Freedericksz transition in twisted ferronematics simultaneously subjected to magnetic and laser fields is studied in this work. Using the elastic continuum theory and Gouchen model for molecular anchoring on the cell support plates, the critical field and the saturation field were calculated as a function of the laser intensity and anchoring strength for two types of ferronematics based on 5CB and CCN-37 liquid crystals.

scholarly journals The Influence of Single-Walled Carbon Nanotubes on the Dynamic Properties of Nematic Liquid Crystals in Magnetic Field

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4031 ◽  
Author(s):  
Cirtoaje ◽  
Petrescu
Keyword(s):  
Magnetic Field ◽  
Liquid Crystals ◽  
Dynamic Properties ◽  
Relaxation Times ◽  
Continuum Theory ◽  
Elastic Continuum ◽  
Walled Carbon Nanotubes ◽  
The Impact ◽  
The Magnetic Field ◽  
Good Agreement

This article aims to study the impact of carbon nanotube dispersions in liquid crystals. A theoretical model for the system’s dynamics is presented, considering the elastic continuum theory and a planar alignment of liquid crystal molecules on the nanotube’s surface. Experimental calculation of the relaxation times in the magnetic field was made for two cases: when the field was switched on (τon), and when it was switched off (τoff). The results indicate an increase of the relaxation time by about 25% when the magnetic field was switched off, and a smaller increase (about 10%) when the field was switched on, where both were in good agreement with the theoretical values.

Effect of the anchoring strength on the phase behaviour of discotic liquid crystals under face-on confinement

2019 ◽  
Vol 31 (10) ◽  
pp. 105101 ◽  
Author(s):  
Daniel Salgado-Blanco ◽  
Enrique Díaz-Herrera ◽  
Carlos I Mendoza
Keyword(s):  
Liquid Crystals ◽  
Phase Behaviour ◽  
Discotic Liquid Crystals ◽  
Anchoring Strength

Effect of the Molecular Structure of Weakly Rubbed Organic Solvent Soluble Polyimides with Trifluoromethyl Moieties on Anchoring Strength of Liquid Crystals

1995 ◽  
Vol 34 (Part 2, No. 9B) ◽  
pp. L1214-L1217 ◽  
Author(s):  
Dae-Shik Seo ◽  
Michinori Nishikawa ◽  
YoshikazuYabe ◽  
Shunsuke Kobayashi
Keyword(s):  
Molecular Structure ◽  
Liquid Crystals ◽  
Organic Solvent ◽  
Anchoring Strength

Selection of Single Harmonic Emission Peak for Producing Isolated Attosecond Pulse via Chirped-UV Combined Field

2019 ◽  
Vol 75 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Hang Liu ◽  
Li-Qiang Feng
Keyword(s):  
High Intensity ◽  
Laser Field ◽  
Laser Intensity ◽  
Potential Method ◽  
Emission Peak ◽  
Harmonic Emission ◽  
Low Intensity ◽  
Isolated Attosecond Pulse ◽  
Intensity Laser ◽  
Selection Of

AbstractA potential method to produce isolated attosecond pulses (IAPs) by using low-intensity chirped-UV combined field has been investigated. The results can be separated into three parts. First, by properly introducing the mid-chirp or down-chirp of the low-intensity laser field, the harmonic cutoff can be extended and achieve the referenced value, which is produced from the high-intensity referenced field. Moreover, the spectral continuum is contributed by a single harmonic emission peak, which is beneficial to produce IAPs. However, the harmonic yield is very low due to the lower driven laser intensity. Second, by properly adding a UV pulse, the harmonic yield can be enhanced and achieve the referenced value due to the UV resonance ionisation. The intensity of the combined field is lower than that of the referenced field, which reduces the experimental requirements for producing high-intensity spectral continuum. Third, with the introduction of the positive or negative inhomogeneous effect of the mid-chirped combined field or down-chirped combined field, respectively, the similar harmonic cutoff and harmonic yield can also be obtained but with a much lower driven laser intensity. Finally, by superposing the harmonics on the spectral continuum, the IAPs with the durations of sub-38 as can be obtained.

Optical method for measuring the azimuthal anchoring strength of liquid crystals using pitch values determined in imperfect samples

2007 ◽  
Vol 102 (6) ◽  
pp. 063108 ◽  
Author(s):  
Tsung-Ta Tang ◽  
Hsin-Ying Wu ◽  
Chia-Jen Lin ◽  
Ru-Pin Pan
Keyword(s):  
Liquid Crystals ◽  
Optical Method ◽  
Anchoring Strength

MODEL FOR MOLECULAR DIRECTOR CONFIGURATION IN A LIQUID CRYSTAL CELL WITH MULTIPLE INTERFACES

2007 ◽  
Vol 16 (02) ◽  
pp. 199-206 ◽  
Author(s):  
LUIGIA PEZZI ◽  
ALESSANDRO VELTRI ◽  
ANTONIO DE LUCA ◽  
CESARE UMETON
Keyword(s):  
Liquid Crystal ◽  
Continuum Theory ◽  
Elastic Continuum ◽  
Crystal Sample ◽  
Input Interface ◽  
Multiple Interfaces ◽  
Top View ◽  
Director Orientation ◽  
Strong Anchoring ◽  
Good Agreement

The study of optical solitons and light filaments steering in liquid crystal requires the utilization of particular cells designed for top view investigation and realized with an input interface which enables the control of the molecular director configuration, preventing light scattering. Actually, the director orientation imposed by this additional interface is estimated only by experimental observations. We report a simple model describing the distribution of the director orientation inside a liquid crystal sample under the anchoring action of multiple interfaces. The model is based on the elastic continuum theory, and strong anchoring is taken into account for boundary conditions. Results are in good agreement with experimental observations.

A Continuum Theory of Chiral Smectic C Liquid Crystals

2008 ◽  
Vol 69 (3) ◽  
pp. 787-809 ◽  
Author(s):  
Maria-Carme Calderer ◽  
Sookyung Joo
Keyword(s):  
Liquid Crystals ◽  
Continuum Theory ◽  
Smectic C
Sign in / Sign up

Export Citation Format

Share Document