Pub Date : 2019-07-03DOI: 10.1080/1358314X.2019.1693094
A. Eremin
The 15th European Conference on Liquid Crystals took place in a lovely town of Wrocław from June 30 till 5 July 2019 (Figure 1). This traditional Conference dates back to 1991 and serves as a forum for the dissemination of ideas in the interdisciplinary field of liquid crystals and soft anisotropic materials. This year, the Conference was chaired by Professor Marzena Tykarska from the Military University of Technology with professor Wiktor Piecek and professor Przemysław Kula as co-chairmen. It was a very successful Meeting, indeed. More than two hundred participants from 31 countries attended and contributed to the program with their presentations, lectures and posters (Figure 2). With five plenary talks and fifteen invited talks, the program was most engaging. It covered a broad spectrum of interdisciplinary areas from the synthesis of liquid crystals to optical and photonic properties and applications in industry, biology, and medicine. The first day followed by the Opening ceremony, Małgosia Kaczmarek from the University of Southampton started the first session delivering a talk on smart, hybrid liquid crystal devices. A very inspiring report explored emerging device technologies for nanoelectromechanical systems with liquid crystals. Application of semiconductors and photo-switchable liquid crystals opens the door to great opportunities to design multifunctional hybrid devices such as self-activated modulators as demonstrated in the presentation. The first session continued on physical properties, including elasto-caloric effect in LC elastomers, complex dynamics in the electro-convection in Hall 1. In the lecture Hall 2, the optical properties of liquid crystals were discussed. In particular, starting with the report on novel optical properties of LC/polymer films (Timothy Bunning), the session continued with the reports on the photo-induced anchoring transitions in cholesteric microdroplets (Sergey Shvetsov). The second session started with an inspiring talk by Victor Reshetnyak on tuning Tamm plasmons using cholesteric liquid crystals electro-optical and flexoelectricoptical effects, fast-response electro-plasmonics and complex re-orientation of the LC during photoalignment. Among the highlights of the evening session, were the presentations by Evaggelia Zavvou on the dielectric properties relationships in the nematic phases of cyano-biphenyl dimers, a talk by Nándor Éber on light-tunable gratings based on flexoelectric effect and a presentation by Alessandro Pianelli ‘Visualization and characterisation of the switching process in dye-doped dual-frequency nematic mixtures’. In the evening many participants attended two interesting tutorial lectures delivered by experienced scientists. The first tutorial presented by Mikhail Osipov was devoted to the molecular theory of liquid crystal ordering in rod-coil diblock copolymers. The next tutorial presented by Slobodan Žumer was about the topological soft matter, which leads from confined and c
{"title":"15th European liquid crystal conference 2019 in Wrocław","authors":"A. Eremin","doi":"10.1080/1358314X.2019.1693094","DOIUrl":"https://doi.org/10.1080/1358314X.2019.1693094","url":null,"abstract":"The 15th European Conference on Liquid Crystals took place in a lovely town of Wrocław from June 30 till 5 July 2019 (Figure 1). This traditional Conference dates back to 1991 and serves as a forum for the dissemination of ideas in the interdisciplinary field of liquid crystals and soft anisotropic materials. This year, the Conference was chaired by Professor Marzena Tykarska from the Military University of Technology with professor Wiktor Piecek and professor Przemysław Kula as co-chairmen. It was a very successful Meeting, indeed. More than two hundred participants from 31 countries attended and contributed to the program with their presentations, lectures and posters (Figure 2). With five plenary talks and fifteen invited talks, the program was most engaging. It covered a broad spectrum of interdisciplinary areas from the synthesis of liquid crystals to optical and photonic properties and applications in industry, biology, and medicine. The first day followed by the Opening ceremony, Małgosia Kaczmarek from the University of Southampton started the first session delivering a talk on smart, hybrid liquid crystal devices. A very inspiring report explored emerging device technologies for nanoelectromechanical systems with liquid crystals. Application of semiconductors and photo-switchable liquid crystals opens the door to great opportunities to design multifunctional hybrid devices such as self-activated modulators as demonstrated in the presentation. The first session continued on physical properties, including elasto-caloric effect in LC elastomers, complex dynamics in the electro-convection in Hall 1. In the lecture Hall 2, the optical properties of liquid crystals were discussed. In particular, starting with the report on novel optical properties of LC/polymer films (Timothy Bunning), the session continued with the reports on the photo-induced anchoring transitions in cholesteric microdroplets (Sergey Shvetsov). The second session started with an inspiring talk by Victor Reshetnyak on tuning Tamm plasmons using cholesteric liquid crystals electro-optical and flexoelectricoptical effects, fast-response electro-plasmonics and complex re-orientation of the LC during photoalignment. Among the highlights of the evening session, were the presentations by Evaggelia Zavvou on the dielectric properties relationships in the nematic phases of cyano-biphenyl dimers, a talk by Nándor Éber on light-tunable gratings based on flexoelectric effect and a presentation by Alessandro Pianelli ‘Visualization and characterisation of the switching process in dye-doped dual-frequency nematic mixtures’. In the evening many participants attended two interesting tutorial lectures delivered by experienced scientists. The first tutorial presented by Mikhail Osipov was devoted to the molecular theory of liquid crystal ordering in rod-coil diblock copolymers. The next tutorial presented by Slobodan Žumer was about the topological soft matter, which leads from confined and c","PeriodicalId":18110,"journal":{"name":"Liquid Crystals Today","volume":"28 1","pages":"70 - 73"},"PeriodicalIF":3.1,"publicationDate":"2019-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/1358314X.2019.1693094","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43097739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-03DOI: 10.1080/1358314X.2019.1693604
R. Morris, Eleni Perivolari
In Quebec City, facing north, from the Pierre-Dugua-De-Mons Terrace (a small hill close to the city centre), there is a particularly spectacular view overlooking the city (see Figure 1). The view h...
在魁北克市,从Pierre Dugua De Mons Terrace(靠近市中心的一座小山)向北看,可以看到俯瞰城市的特别壮观的景色(见图1)。视图h。。。
{"title":"Report on the 18th Optics of Liquid Crystals Conference, 8th-13th September 2019, Quebec City","authors":"R. Morris, Eleni Perivolari","doi":"10.1080/1358314X.2019.1693604","DOIUrl":"https://doi.org/10.1080/1358314X.2019.1693604","url":null,"abstract":"In Quebec City, facing north, from the Pierre-Dugua-De-Mons Terrace (a small hill close to the city centre), there is a particularly spectacular view overlooking the city (see Figure 1). The view h...","PeriodicalId":18110,"journal":{"name":"Liquid Crystals Today","volume":"28 1","pages":"76 - 81"},"PeriodicalIF":3.1,"publicationDate":"2019-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/1358314X.2019.1693604","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45904828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-03DOI: 10.1080/1358314X.2019.1653454
M. Nagaraj
Oscillating dynamics of cis-trans isomerisation of the azobenzene can boost free volume generation in liquid crystal polymer networks. As such excess volume can influence the guest molecules’ motion by influencing the space around them, the isomerisation process could be used for applications involving molecular transport. The paper by Cao et al., reports the investigation of a photomechanical effect in a polymer network for molecular transport purposes. The transport of 5CB liquid crystal through a chiral nematic polymer network consisting of azobenzene units is investigated. ~28% increase in diffusion is observed from light OFF to light ON state. The influence of polarisation of the incident light on the diffusion process is studied.
{"title":"Research news","authors":"M. Nagaraj","doi":"10.1080/1358314X.2019.1653454","DOIUrl":"https://doi.org/10.1080/1358314X.2019.1653454","url":null,"abstract":"Oscillating dynamics of cis-trans isomerisation of the azobenzene can boost free volume generation in liquid crystal polymer networks. As such excess volume can influence the guest molecules’ motion by influencing the space around them, the isomerisation process could be used for applications involving molecular transport. The paper by Cao et al., reports the investigation of a photomechanical effect in a polymer network for molecular transport purposes. The transport of 5CB liquid crystal through a chiral nematic polymer network consisting of azobenzene units is investigated. ~28% increase in diffusion is observed from light OFF to light ON state. The influence of polarisation of the incident light on the diffusion process is studied.","PeriodicalId":18110,"journal":{"name":"Liquid Crystals Today","volume":"28 1","pages":"54 - 55"},"PeriodicalIF":3.1,"publicationDate":"2019-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/1358314X.2019.1653454","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43816887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-03DOI: 10.1080/1358314X.2019.1654108
N. Trbojevic
The 35 annual meeting of the British Liquid Crystal Society (BLCS) took place at the University of Leeds (Figure 1, top) from Monday 15 April to Wednesday 17 April 2019. The conference was organised by Dr Mamatha Nagaraj and Professor Cliff Jones (Figure 1, bottom) from the Leeds Soft Matter Physics group, who welcomed nearly one hundred attendees from countries across the Globe, including USA, India, Pakistan, China, Czech Republic and Germany. This year’s BLCS conference was unique as a special Symposium on lyotropic liquid crystals (L3C) was held prior to the start of the conference. The Symposium was organised by Mariam Hussain, a final year PhD student from the School of Chemical Engineering at the University of Leeds. Mariam’s goal was to attract a broader range of attendees to the BLCS conference, especially those working in the field of lyotropic liquid crystals. In addition, attendees of the Symposium would gain a detailed understanding of lyotropic liquid crystals, as a greater emphasis is often placed on thermotropic liquid crystal research. In this respect, the Symposium was a success, since it encouraged interactions between those working in thermotropics and lyotropics, and was evident from both the high attendance and the number of lyotropic-based presentations at the main conference. The Symposium featured a series of lectures given by leading researchers in the field of lyotropics. Professor Gordon Tiddy from the University of Manchester opened the Symposium with a lecture that introduced the fundamentals of lyotropic liquid crystals and the self-assembling supramolecular structures they form, placing an emphasis on surfactants. Further, Dr Arwen Tyler (University of Leeds), Professor John Seddon (Imperial College London) and Professor Mark Wilson (Durham University) presented the fascinating science behind the phases, theoretical simulations and applications of lyotropic liquid crystals. Finally, Dr John Lydon from the University of Leeds closed the Symposium with a presentation on tactoids and their occurrence in colloidal lyotropic sols and, in particular, their relationship to the shape of red blood corpuscles. The Symposium was followed by lunch, whereby further discussions and networking between participants took place (Figure 2). The BLCS conference began on Monday afternoon after the L3C Symposium, whereby all attendees were warmly welcomed by Cliff and Mamatha. Cliff pointed out that the conference was exactly 51 years to the day since Leeds hosted a special meeting of the Faraday Society on Liquid Crystals, where (later, Sir) Charles Frank was to present his ground-breaking paper on elasticity and defects in liquid crystals. Research topics being presented at the current conference were across all disciplines: from colloids, lyotropics and materials, to theory and devices. The oral presentation sessions were opened with the plenary lecture by Professor Ivan Smalyukh from the University of Colorado Boulder, USA, titled ‘
{"title":"Report of the British Liquid Crystal Society annual meeting, The University of Leeds, 15th – 17th April 2019","authors":"N. Trbojevic","doi":"10.1080/1358314X.2019.1654108","DOIUrl":"https://doi.org/10.1080/1358314X.2019.1654108","url":null,"abstract":"The 35 annual meeting of the British Liquid Crystal Society (BLCS) took place at the University of Leeds (Figure 1, top) from Monday 15 April to Wednesday 17 April 2019. The conference was organised by Dr Mamatha Nagaraj and Professor Cliff Jones (Figure 1, bottom) from the Leeds Soft Matter Physics group, who welcomed nearly one hundred attendees from countries across the Globe, including USA, India, Pakistan, China, Czech Republic and Germany. This year’s BLCS conference was unique as a special Symposium on lyotropic liquid crystals (L3C) was held prior to the start of the conference. The Symposium was organised by Mariam Hussain, a final year PhD student from the School of Chemical Engineering at the University of Leeds. Mariam’s goal was to attract a broader range of attendees to the BLCS conference, especially those working in the field of lyotropic liquid crystals. In addition, attendees of the Symposium would gain a detailed understanding of lyotropic liquid crystals, as a greater emphasis is often placed on thermotropic liquid crystal research. In this respect, the Symposium was a success, since it encouraged interactions between those working in thermotropics and lyotropics, and was evident from both the high attendance and the number of lyotropic-based presentations at the main conference. The Symposium featured a series of lectures given by leading researchers in the field of lyotropics. Professor Gordon Tiddy from the University of Manchester opened the Symposium with a lecture that introduced the fundamentals of lyotropic liquid crystals and the self-assembling supramolecular structures they form, placing an emphasis on surfactants. Further, Dr Arwen Tyler (University of Leeds), Professor John Seddon (Imperial College London) and Professor Mark Wilson (Durham University) presented the fascinating science behind the phases, theoretical simulations and applications of lyotropic liquid crystals. Finally, Dr John Lydon from the University of Leeds closed the Symposium with a presentation on tactoids and their occurrence in colloidal lyotropic sols and, in particular, their relationship to the shape of red blood corpuscles. The Symposium was followed by lunch, whereby further discussions and networking between participants took place (Figure 2). The BLCS conference began on Monday afternoon after the L3C Symposium, whereby all attendees were warmly welcomed by Cliff and Mamatha. Cliff pointed out that the conference was exactly 51 years to the day since Leeds hosted a special meeting of the Faraday Society on Liquid Crystals, where (later, Sir) Charles Frank was to present his ground-breaking paper on elasticity and defects in liquid crystals. Research topics being presented at the current conference were across all disciplines: from colloids, lyotropics and materials, to theory and devices. The oral presentation sessions were opened with the plenary lecture by Professor Ivan Smalyukh from the University of Colorado Boulder, USA, titled ‘","PeriodicalId":18110,"journal":{"name":"Liquid Crystals Today","volume":"28 1","pages":"48 - 53"},"PeriodicalIF":3.1,"publicationDate":"2019-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/1358314X.2019.1654108","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46129925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-03DOI: 10.1080/1358314X.2019.1653588
Dae‐Yoon Kim, K. Jeong
ABSTRACT Stimuli-responsive soft matters have been recognised by many scientists and engineers as very important because of their inherent characteristics in response to environmental changes. In particular, there has been much progress over the last few years on light-responsive soft matters that can respond remotely. By controlling the packing behaviours and the physical properties of the photoresponsive liquid crystal (LC) molecules, the application field is expanding, including the use in flexible polarisers, patterned objects, logic devices, biomimetic photonic crystals and energy harvesting materials. This review discusses the general concept of azobenzene-based LC compounds from small molecules to macromolecules and their corresponding structural evolutions in solid states. Finally, we identify the challenges faced in the research of photoresponsive organic materials and present future applications.
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Pub Date : 2019-01-02DOI: 10.1080/1358314X.2019.1624411
M. Nagaraj
There is an increasing demand for high-performance functional devices with liquid crystals to control and modulate THz waves. In such cases, liquid crystal devices employing external magnetic field to control optical effects are preferred as they do not require ITO electrodes which are polarization selective. Ji et al. report the optical and magneto-optical properties of mixtures of liquid crystals having ferromagnetic nanoparticles in the THz regime. Particularly, magnetically induced birefringence characteristics of the composite systems for THz liquid crystal phase shifter are discussed. A phase shift range between ne and no, by changing the magnitude of the external magnetic field without changing its direction has been achieved. The interaction between magnetic cluster chains formed by the ferroparticles, with the liquid crystal director and the external magnetic field, is explained theoretically by comparing the surface anchoring force and the magnetic moment in the dynamic system.
{"title":"Research news","authors":"M. Nagaraj","doi":"10.1080/1358314X.2019.1624411","DOIUrl":"https://doi.org/10.1080/1358314X.2019.1624411","url":null,"abstract":"There is an increasing demand for high-performance functional devices with liquid crystals to control and modulate THz waves. In such cases, liquid crystal devices employing external magnetic field to control optical effects are preferred as they do not require ITO electrodes which are polarization selective. Ji et al. report the optical and magneto-optical properties of mixtures of liquid crystals having ferromagnetic nanoparticles in the THz regime. Particularly, magnetically induced birefringence characteristics of the composite systems for THz liquid crystal phase shifter are discussed. A phase shift range between ne and no, by changing the magnitude of the external magnetic field without changing its direction has been achieved. The interaction between magnetic cluster chains formed by the ferroparticles, with the liquid crystal director and the external magnetic field, is explained theoretically by comparing the surface anchoring force and the magnetic moment in the dynamic system.","PeriodicalId":18110,"journal":{"name":"Liquid Crystals Today","volume":"28 1","pages":"2 - 3"},"PeriodicalIF":3.1,"publicationDate":"2019-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/1358314X.2019.1624411","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42115598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}