Written by Hu Wei
Character introduction
Professor Lu Yanqing
Vice president of Nanjing University, distinguished professor of Changjiang Scholars, winner of national Distinguished Young Scholars fund, leader of science and technology innovation of "ten thousand talents plan", member of American Optical Society, member of Chinese Optical Society, member of Chinese Optical Society, member of Chinese Physical Society and head of liquid crystal branch Executive editor of letters, editorial board member of LCD and display, science and technology guide, and member of "world class scientific and technological journal Construction Expert Committee" of China Association for science and technology.
In 1991 and 1996, he received bachelor's degree and doctor's degree respectively from the Department of physics of Nanjing University, and then he stayed in school to teach. Since 2000, Lu Yanqing has gone to the United States and turned his work to the field of applied engineering technology. He has successively held R & D and management positions in a number of high-tech companies and accumulated rich practical experience in the R & D and production of optoelectronic products. At the end of 2006, Lu Yanqing was hired to return to Nanjing University. He presided over national key R & D projects, 863, 973, NSFC and many other national research projects.
Mainly focusing on liquid crystal optics, nonlinear optics, optical fiber optics, etc., he has published more than 200 papers in science, PRL, NC, am and other journals, and has been cited for more than 5000 times. More than 100 patents have been applied for, including more than 70 authorized patents and 5 transferred patents.
In 1999, Lu Yanqing was selected as the leader of research achievements in "top ten scientific and technological progress of Chinese institutions of higher learning", "top ten news of China's basic research", etc.; one of the winners of the first prize project of 2006 National Natural Science Award "design, preparation, performance and application of dielectric superlattice materials"; the team research achievements were selected into the top ten optical progress of China in 2018 and 2019; students were trained for three times of honor Won the "Wang Daheng optical award university student optical Award" of China Optical Society.
Professor Hu Wei
Professor and doctoral director of Nanjing University, winner of National Excellent Youth Fund and winner of Jiangsu outstanding youth fund.
In 2004, he obtained his bachelor's degree from Northeast Forestry University, and in 2009, he obtained his doctor's degree from Jilin University. In the same year, he worked as a lecturer, associate professor and professor in Nanjing University. In 2011, he went to CDR of Hong Kong University of science and technology for a short visit.
Hu Wei focuses on the liquid crystal as a soft material system, and has carried out research on three aspects: liquid crystal assembly super structure, light addressing liquid crystal dimming and liquid crystal optical elements. He has been working in NAT. Commun., light SCI. Appl., adv. mater, More than 100 papers have been published in ACS Nano and other journals, cited more than 2500 times, h index 30 (Google Scholar); more than 70 invention patents have been applied for, 7 chapters of monograph have been written, and more than 30 conference reports have been invited; he has presided over many projects such as NSFC, Ministry of education / Jiangsu provincial fund, national defense pre research and enterprise technology development.
In 2016, he was selected by liquid crystal as the representative of young scholars to write for his 30th anniversary special issue. In 2017, he was selected as the first Zhongying young scholars, and his team's research achievements were successively selected as the top ten optical progress of China in 2018 and 2019. Hu Wei is a member of the Committee of liquid crystal branch of Chinese physical society, a member of the young Editorial Committee of China laser magazine, a member of the Editorial Committee of liquid crystal and display, SCI. Rep., opt. Express, Editor of chin. Opt. Lett. Special issue and evaluation expert of many domestic and foreign fund organizations; CO sponsor and sponsor of the first session of China LCD Youth Scholars forum, and served as chairman / CO chairman / member of many domestic and foreign academic conference organizing committee / procedure Committee.
Collection of important achievements
The following chapters are divided into three parts:
Part I optically controlled liquid crystal domain engineering;
Part II light addressable liquid crystal dimming technology;
Part III liquid crystal terahertz and optical communication elements.
01 optically controlled liquid crystal domain engineering
1.1 four dimensional imaging of asymmetric liquid crystal microlens array ACS Nano visualization imaging is very important in basic research and technical application. In order to obtain the three-dimensional spatial information of objects, expensive testing equipment and complex technical means are usually needed. As another physical dimension of light, polarization plays an important role in material characterization, remote sensing, biological information interaction and other fields. However, it is still a challenge to simply and efficiently detect the space and polarization information of the target object.
Hu Wei and Lu Yanqing team reported a technology of four-dimensional information visualization imaging based on asymmetric liquid crystal super structure generated by alignment induced self-assembly. Through the design of microlens unit size and orientation distribution, not only the depth and polarization information of the object to be measured is extracted efficiently, but also the function of microlens array multiplexing / demultiplexing depth and polarization information is given. This kind of asymmetric microlens array is conducive to the miniaturization and integration of devices, which is consistent with the development trend of photon technology, and has a broad application prospect in optoelectronic devices, optical communication and other fields.
Ling-Ling Ma,? Sai-Bo Wu,? Wei Hu,* Chao Liu, Peng Chen, Hao Qian,Yan-Dong Wang, Li-Feng Chi and Yan-Qing Lu* "Self-assembled asymmetric microlenses for four-dimensional visual imaging" ACS Nano 2019, 13(12), 13709-13715.
?https://pubs.acs.org/doi/10.1021/acsnano.9b07104
1.2 the optical and electrical manipulation of self-assembled spiral superstructures and the ubiquitous superstructures in the nature of science advances play an important role in the physical and chemical properties of materials. Cholesteric liquid crystals can form one-dimensional helical superstructures with multiple response capabilities through molecular self-assembly and exhibit Bragg reflection properties. The pitch and the corresponding reflection band can be controlled by temperature and other external fields, but there are still some problems to be solved, such as low control efficiency, narrow spectral dynamic range, single controllable parameters, poor structural stability and so on.
Zheng Zhigang, Lu Yanqing, Li Quan, etc. obtained a stable and reliable light responsive liquid crystal material system through the delicate design of photosensitive chiral molecular motor and the matching of liquid crystal elastic free energy. The stable, dynamic and reversible control of the cholesteric superstructures between the planar helix, the inclined helix, the untwisted state and their respective backhand helices is realized by the external photoelectric joint modulation. Furthermore, the cholesteric liquid crystal laser with controllable external field and continuous wide spectrum modulation is realized. The research results are expected to open up new technology directions in controllable chiral filtration and expand new optical applications based on cholesteric spiral super structure control. Cong-long Yuan,? Wenbin Huang,? Zhi-gang Zheng,?,*Binghui Liu, Hari Krishna Bisoyi,Yannian Li, Dong Shen, Yanqing Lu*, Quan Li,*“Stimulated transformation of soft helix among helicoidal, heliconical, andtheir inverse helices” Science advances 2019, 5, eaax9501.
?https://advances.sciencemag.org/content/5/10/eaax9501.abstract
1.3 research progress of multi-layer super structure of optically controlled liquid crystal there are many wonderful phenomena in nature, such as the structural color of butterfly wings. The results show that these phenomena are all originated from the complex and delicate multi-level super structure inside the organism. This kind of ordered super structure plays an important role in functional materials. In recent years, liquid crystal has attracted more and more attention because of its excellent self-assembly and stimulus response. Among them, it is an important direction to realize the long-range order of microstructure by using the self-assembly behavior of light-controlled liquid crystal.
Li Quan and Lu Yanqing co authored the report on the research progress of the multi-layer super structure of the light-controlled liquid crystal, which focused on the research progress of the multi-layer super structure of the light-controlled liquid crystal in the three kinds of liquid crystal, i.e. the near crystal phase, the one-dimensional helical cholesteric phase and the blue phase of the cubic lattice, and introduced the specific application of these super structures in the field of photonics, and from the material improvement, mechanism explanation, the application of the light driven super structure, etc The future research direction is prospected. It is hoped that more researchers will work together to open a door for new intelligent optical materials and explore more new applications.
Ling-Ling Ma?, Wei Hu?, Zhi-Gang Zheng?, Sai-Bo Wu, PengChen, Quan Li* and Yan-Qing Lu* "Light-activated liquid crystalline hierarchical architecture toward photonics" Adv. Opt. Mater. 2019, 1900393.
?https://onlinelibrary.wiley.com/doi/abs/10.1002/adom.201900393
1.4 the orderliness of light-controlled blue phase soft lattice orientation, micromanipulation and patterned advanced materials structure explain the magic and harmony of nature. Crystal is a typical ordered structure, which is widely used in the fields of electronics and photonics. The order will directly affect the quantum manipulation of crystal materials, so it is very important to realize the ordered arrangement of lattice. However, it is difficult to control the generation of dislocations or defects, so it is still a challenge to realize the micro localization of crystal faces and the formation of periodic or quasi periodic patterned lattice arrangement with order disorder alternation.
Lu Yanqing, Li Guoqiang, Li Quan, etc. have successfully realized arbitrary microcrystalline patterns such as periodic lattice, concentric ring, fork grating and digital pattern by using dynamic mask light matching technology, which directly proves the decisive influence of orientation control on lattice directivity and order. Because the reflectivity of the ordered and disordered regions of the blue phase liquid crystal is significantly different from that of the specific frequency light, and it shows the characteristics of weak electric regulation, the specially customized blue phase lattice pattern can be used as the diffraction optical element of amplitude modulation. The realization of lattice arrangement order, micromanipulation and patterning in the research results will bring important enlightenment to materials, optics and other fields, and show the value of engineering application.
Zhi-gang Zheng,? Cong-long Yuan,? Wei Hu,? Hari Krishna Bisoyi, Ming-jie Tang, Zhen Liu, Pei-zhi Sun, Wei-qiang Yang, Xiao-qian Wang,Dong Shen, Yannian Li, Fangfu Ye, Yan-qing Lu*,Guoqiang Li*, and Quan Li*"Light-patterned crystallographic direction of a self-organizedthree-dimensional soft photonic crystal" Adv. Mater. 2017, 29, 1703165.
?https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.201770301
1.5 "origami" in molecular layer: the super structure of near crystal phase focal cone domain controls the material structure of advanced materials, which is a bridge between the micro and macro world, and plays an important role in the material system. The assembly behavior of liquid crystal can be controlled by external field, so it is an excellent assembly unit. Among them, the near crystalline liquid crystal has attracted much attention because of its ability of self-assembly to form ordered multi-layer super structure, which has great potential in the fields of beam control, super hydrophobic surface and so on. However, at present, there are still some problems such as low efficiency, complex operation, limited control dimension and so on.
Hu Wei, Chi Lifeng, Lu Yanqing and other partners introduced the dynamic mask photoorientation technology into the near crystal phase liquid crystal super structure control, combined the "top-down" patterned orientation with the "bottom-up" liquid crystal molecular assembly, put forward the concept of molecular layer "origami", and realized the full dimensional control of the near crystal phase liquid crystal focal cone domain super structure. This kind of focal cone domain breaks the rotational symmetry of toroidal focal cone domain and presents a novel polarization dependent asymmetric diffraction phenomenon. The research results enhance people's ability to design and construct multi-layer super structure materials, which is an important progress in the field of soft material and nanotechnology.
Ling-Ling Ma, Ming-Jie Tang, Wei Hu*, Peng Chen, Shi-Jun Ge, Ze-Qun Cui, Lu-Jian Chen,Hao Qian, Li-Feng Chi*, Yan-Qing Lu* "Smectic layer origami viapreprogramed photoalignment" Adv. Mater. 2017, 29, 1606671.
?https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.201606671
1.6 precise manipulation of cholesteric liquid crystal spiral superstructures
Advanced Optical Materials
Helix knot