Joint Seminar by ECE, SID and SKL - Soft-Nano Composites: Functional Liquid Crystals Aiding Dreamy Invisibility Technology
Currently, there have been strategic approaches to develop an entirely different class of functional materials, called Nano-Soft Composites. Such efforts have emerged basically to amalgamate the themes of nanoparticles (NPs) and liquid crystals (LCs) by realizing hybrid NP-LC motifs through the design and synthesis. In particular, the organic ligands (as capping agents), capable of exhibiting LC behaviour, are bound to the central NPs to realize nano-soft composites. Notably, these hybrids display fluidity, double refraction, and strong optical resonance arising from localized surface plasmon. These unique combined features are highly promising in photonics, sensors, photovoltaics, hyperlensing etc. Thus, we have designed, prepared, and characterized several series of single-component gold NP-LC composites. The synthetic procedures employed are straightforward, hassle-free, and high yielding. Precisely, the reduction of Au(III) to Au(0) by optically active (chiral) LC primary amines and their subsequent binding to the NPs yield the target NP-LC materials. The standard spectroscopic methods, SEM/TEM imaging, AFM technique, EDX mapping, X-ray diffraction (XRD) etc., are used to elucidate the structure of the hybrids. The microscopic, calorimetric and XRD studies were employed to determine the LC behaviour of these NPs prepared. The results of these investigations, coupled with CD spectral data confirm their self-organization into lamellar (LC) structure having handedness (chirality). In this study, the tunable epsilon-near-zero (ENZ) behavior brought about by an optical field has been demonstrated.
Dr. Yelamaggad obtained his M.Sc. and Ph.D. degrees in Organic Chemistry from Karnataka University, Dharwad. He carried out his postdoctoral research for three years at the Department of Organic Chemistry, Indian Institute of Science, Bangalore. Later, for a couple of years, he was a senior scientist in the private chemical industry's R & D division. Then he moved to the Department of Applied Chemistry, National Chiao Tung University, Taiwan to conduct postdoctoral research. Ever since 1997, he has been a Scientist at the Centre for Nano and Soft Matter Sciences (CeNS), Bangalore. His work focuses on soft matter, nanomaterials, nano-soft composites, and other closely related functional materials that are promising from the viewpoints of both fundamental research and advanced technology. Dr. Yelamaggad has made many noteworthy scientific contributions in the field of liquid crystals with his journal research publications numbering over 225. Besides, he has ten national and international patents to his credit. He has guided over nine Ph. D. students, five postdoctoral researchers, and several project assistants. He has been the principal investigator for research projects sponsored by governmental agencies. His research accomplishments have been well recognized at the national and international levels. He has presented over 320 invited lectures and written reviews in journals and textbooks. He has been the referee to the vast majority of leading international chemistry journals. As an invited scientist, he has visited several prestigious scientific institutions in USA, Canada, UK, Japan, Korea, Hungary, Bulgaria, etc, both to share his ideas in various seminars and to have research collaborations.
He has been the recipient of the State Government’s, National & International awards namely,
1. Japanese Government’s JST Fellowship for the year 2000
2. Japanese Government‘s JSPS Fellowship for the years 2002 & 2003
3. Govt. of Karnataka’s Sir C. V. Raman Young Scientist Award for the year 2005
4. The Royal Society’s, London, Visiting Fellowship for the year 2007
5. MRSI (Materials Research Society of India) Medal-2019, Indian Institute of Science, Bangalore
6. FRSC (Fellow of the Royal Society of Chemistry) award from Royal Society of Chemistry, London, UK for the year 2019.
7. Silver Medal, Chirantan Rasayan Sanstha®, Vidyasagar University, West Bengal (2020)
8. CRSI (Chemical Research Society of India) Medal, Indian Institute of Science, Bangalore (2021)
Recently he has been listed in the World Ranking of Top 2 % Scientists from India. He has been elected as an Executive Member of RSC, Deccan Section and Dr. Yelamaggad has also been active in educating college students and teachers about liquid crystal science and technology through his inspiring talks at refresher courses and science popularization programs.