Three scientists from IISER Pune—G.V. Pavan Kumar, Sujit Ghosh, and M. Jeganmohan—have been awarded the Indian National Science Academy’s Medals for Young Scientists for 2013. These medals, which will be presented in December this year, recognize promising young investigators in India who have made notable research contributions in science and technology. We have interviewed here these IISER Pune faculty members to learn about their award winning research and their experience setting up independent research groups at the institute.
With a PhD from the Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore and postdoctoral research at the Institute of Photonic Sciences (Spain) and Purdue University (U.S.), G.V. Pavan Kumar joined IISER Pune in May 2010 as a Ramanujan Fellow in Physics and Chemistry. He has since built around him a group of motivated undergraduate and graduate students working in the area of plasmonics and nanophotonics—the study of the interaction of light with materials and molecules at the micro and nanoscales.
Pavan Kumar has been awarded the INSA Young Scientist Medal in April this year for his work on the physics of surface plasmons in serially coupled plasmonic nanowires. He talks here about his work, lab and team.
SK: What are your new research findings that brought you this recognition?
PK: In the last 3 years at IISER Pune, the focus of my research has been on physics and applications of surface plasmons. My research group is currently working on questions pertaining to propagation and localization of light at sub-wavelength scale. One of important plasmonic nanostructures that we are currently studying is the serially-coupled plasmonic nanowires. This geometry, which was innovated in my lab at IISER Pune, has a unique feature of facilitating the propagating and localized plasmons on a single platform (Applied Physics Letters 100:43108 (2012)). At a fundamental level, this serially coupled geometry resembles coupled-resonant systems that are extensively studied in various branches of physics. Furthermore, we have shown that the coupled nanowires can be utilized to create and control optical polarization states on-demand (Applied Physics Letters 101:111111 (2012)), which may have implications in nanophotonics and chip-scale quantum optics.
SK: What aspects of IISER Pune made this possible?
PK: The research support at the institute, both at the monetary and intellectual levels, has been excellent. The equipment that we have obtained for research has been ‘world-class’, and the general infrastructure is good. What I like about IISER Pune is the emphasis and seriousness towards research and an informal mindset of the people. This has really made life easy and enjoyable at IISER Pune.
SK: From an individual researcher to managing a research group: How did you make this transition?
PK: The students in my research group have been very enthusiastic about research, and that has been a very important thing for me. On a day-to-day basis I interact with them, and they share the excitement of their research with me, and that is inspiring. The undergraduate research students have played a very important role in my research and have been lead authors in some of the research papers from my group. Building a team of young researchers has been a new experience for me. Personally, I have learnt that time is very precious, and utilizing it properly can make a big difference in research and teaching.
SK: How are you chalking your future research directions?
PK: The field of plasmonics has emerged as an interesting and important research area with relevance to nanophotonics, nano-optics, nano-spectroscopy, quantum optics, bioimaging etc. Many interesting research questions, both at fundamental and application levels, are emerging. We intend to explore problems in plasmonics that are experimental and theoretical in nature. For the next few years, I intend to focus on the following research areas.
1) Plasmonic nano-antennas: Antenna effects such enhancement, propagation and directional emission of light at nanoscale are now possible, thanks to plasmonic nano-architectures. We will explore questions pertaining to behavior of linear and non-linear surface plasmons in spatial, temporal and spectral domains, and how they can be harnessed as optical nano-antennas.
2) Optics of single emitters: Molecules, quantum dots and a variety of plasmonic nanoparticles can function as individual sources of light when isolated. Their emission characteristics can be classical or quantum in nature depending on various controllable parameters such as local environment, excitation field intensity and polarization. We intend to experimentally probe such single emitters under isolation and perturbation.
Sujit K. Ghosh obtained his PhD from Indian Institute of Technology (IIT) Kanpur, India in 2006. He then spent three years at Kyoto University, Japan as a JSPS and CREST postdoctoral fellow before joining IISER Pune in 2009.
He has been awarded the INSA Young Scientist Medal earlier this year for his significant contribution toward the design and synthesis of functional metal organic frameworks (MOFs) for ion and explosive sensing.
SK: Can you describe the work that gave you this recognition?
SG: I would like to highlight three different fields of research work that we are currently pursuing in our lab.
1. Detection of nitro explosive: Selective detection of explosives is an issue of international concern. We have designed and synthesized a metal-organic framework that can selectively detect one highly explosive compound in the presence of other chemically related explosive and non-explosive compounds. Another important aspect is that this compound is quite stable in the presence of water. So the current compound is also potentially useful for tracing buried and underwater explosives near ordnance bases for environmental monitoring.
2. Tunable Luminescence: Stimuli responsive luminescent materials are of great interest because of their potential applications in chemical sensors. An important aspect from clean environment point of view is treating waste from nuclear plants which contain a lot of hazardous anions. We have designed and synthesized a luminescent compound with cationic framework having free anions in its channels. It shows selective anion exchange with tunable luminescence behavior based on size, shape and electronic interactions with the anions. This can be potentially useful for detection and removal of hazardous anions from radioactive waste.
3. Carbon capture and storage: Carbon capture and storage (CCS), where carbon dioxide is removed from industrial fuel gases has attracted considerable attention as it is technologically feasible and could play a significant role in reducing greenhouse gas emissions which mainly contributes to global warming causing climate changes. We have synthesized compounds which show high CO2 selectivity over other gases and stable in water vapour, which makes the compound a promising candidate for industrial gas separation application.
SK: What was your experience of setting up a lab at IISER Pune like?
SG: Setting up an advanced lab with excellent research facilities is the foundation for quality research. With excellent financial and administrative support from our institute, starting new research lab was extremely well-organized and helped in quickly establishing a smooth workflow.
SK: How did you learn to manage and mentor students?
SG: Fortunately, I came across two excellent research supervisors from whom I have learnt the art of managing and mentoring students as well as motivating them to do their best. In addition, I get good insights from my colleagues and try to take their good approaches. Finally, I learn every day from my own experiences and enjoy my role as a mentor.
SK: Where to from here in terms of research goals?
SG: Our overall goal is to develop novel functional porous materials for industrial, environmental and energy applications.
M. Jeganmohan obtained his PhD from the National Tsing Hua University, Hsinchu, Taiwan in 2005. He was a postdoctoral fellow at National Tsing Hua University, Taiwan and later at Ludwig-Maximilians-Universitat, Munich, Germany before joining IISER Pune in 2011.
Jeganmohan has been awarded the INSA Young Scientist Medal for his work on synthetic applications of organometallic chemistry—specifically, on ruthenium-catalyzed selective C-H bond functionalization of substituted aromatics, heteroaromatics and alkenes. He talks here about his research and mentoring philosophy.
SK: What is the focus of your research?
MJ: Organic compounds consist of chemical bonds with carbon atoms–these could be C-C, C-N, C-O etc. The main focus of the lab is how to make these bonds and connect two moieties in an easy manner.
In order to connect two moieties, one has to break a few existing bonds and generate new ones. Cross coupling reactions catalyzed by elements like palladium have make it a lot more easier to make C-C bonds; this reaction has made it to the 2010 Nobel Prize in Chemistry. However, in these reactions, C-X (X = I, Br, OTf, SiR3, SnR3, B(OH)3, etc.) have been used to make new C-C bonds. Breaking a bond between a carbon and X is quite easy. But, breaking a bond between a carbon and hydrogen is very difficult as it requires a lot of energy. However, if one were to replace the H with a metal, it is easy to break the carbon-metal bond. And one can then proceed with making a new bond and connecting two moieties.
In our lab, we are trying to devise new ways (C-H bond functionalization) of avoiding the middle steps involved in the above process, such as replacing the C‑X with an alternate element, en route to connecting two moieties. This allows minimal loss of atoms and reduces usage of organic solvents which are toxic. Another requirement that we try to meet is that our reactions should not require an inert atmosphere. In essence, we work toward devising reactions that are atom economical and environment friendly.
We are developing new, simple routes for synthesizing natural compounds that can then be taken up by biologists and materials chemists for testing their use in various potential applications.
SK: How was your transition to becoming an independent investigator?
MJ: I strongly believe that the kind of equipment, facilities and support that I received at IISER Pune was instrumental in setting up a lab at the institute at a great pace and has allowed me to start research work without any delays on the logistics front. IISER Pune being an undergraduate institute and with the Chemistry PhD program being already functional, students started joining the lab, and within a few months, we had a stable workflow.
As for managing a group and training students, I work along with the students to convey fundamental aspects of research such as asking the right questions and troubleshooting through the project. I generally discuss with students about their research interests, so that they can take up a line of work that interests them within the broad framework of my lab’s goals. This arrangement provides an incentive to the students and helps generate synergy.
SK: How do you envision your future research?
MJ: We would like to explore specific applications for the molecules generated in the lab in materials chemistry and in pharmaceutical areas.
–Article and interviews put together by K.N. Ganesh and Shanti Kalipatnapu