We end the year with Dr. Purohit’s interview here at The Science and Engineering Cafe . While the website is only 5 months old, I think we covered a wide range of plasma topics and applications: from low pressure rf plasmas to atmospheric dielectric barrier discharges (DBDs) for water sterilization and the deposition of materials.
Our Scientist of the Week is Dr. Viswas Purohit. Viswas is a very accomplished engineer who is active on professional discussion boards. What caught my attention was his willingness to volunteer some of his time to provide comments and educate others on topics related to plasma technology. In his interview, he talks about a fun moment in his career, provides advice to students now entering and field and discusses his future plans.
Enjoy the interview! Happy Holidays!
1. Vishwas S. Purohit et.al. , Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Volume 266, Issue 23, December 2008, Pages 4980-4986
2. Vishwas Purohit et.al. , Applied Surface Science, Volume 257, Issue 16, 1 June 2011, Pages 7184-7189
3. Vishwas S. Purohit et.al. Vacuum, Volume 83, Issue 2, 26 September 2008, Pages 435-443
Dr. Viswas Purohit’s Interview
1) What advice would you give to someone who is now entering the field?
For someone newly entering into the field of plasma research, I would suggest they study the latest research papers extensively. Also, it is important for the new researcher to have an up-to-date knowledge of the latest developments in a secondary field of interest, such as chemistry, technology, programming, science fiction etc. The day will come where you will be able to correlate your two fields of interest to create something new and magical. I remember reading Steve Jobs had an interest in calligraphy during his early days which he would later use to help design the fonts in Apple systems. Also, as someone new, it is very important you collaborate and meet with other people working in similar fields. I recommend you attend as many conferences as possible which will give a broader view and different perspectives to your research issues. Try to be as self-independent as possible in experiments or simulations and get full control of your project since becoming dependent on others for system design or coding for a prolonged period of time, can delay the rate of progress. My suggestions would be to learn as much as possible so you can improve your CV as well as be market ready when you decide to take the next career leap.
2) What made you choose plasma as your field of study?
When I was studying for my bachelors degree in Electronics, I learnt a lot about different electronic circuits and how they work. The next semester I learnt about integrated circuits and I was very intrigued by their complex manufacturing process. I also learnt about etching, deposition and the processes behind it. I noticed that the technology behind semiconductor chip fabrication relied heavily on plasma and I started investigating where all plasmas are used. It turned out that plasma touched almost all parts of human life including medicine, energy, electronics, food technology, automobile industry, fluorescent lamps, surface treatments, destruction of toxic waste, cutting, packaging, life sciences, textiles etc. This piqued my interest tremendously and I decided to contribute something in this interesting field of research. When studying for my masters degree in Electronics, my favorite subject was VLSI fabrication. Although I studied Electronics, my main motive was an in-depth study of the material science & physics behind chip fabrication and the processes involved. My interest for material processing, especially for semiconductor chip fabrication, caused me choose plasma as my field of study.
3) Describe a fun moment in your career.
I remember a time when our group had to clean out one of our old labs and came across some old vacuum tubes. I told my PhD supervisor that it would be a shame to throw it away and asked for permission to study them. My supervisor told me, ‘Why don’t you break one and see the material contents using EDX?’ I did exactly that and found the metal to be made of 95% Nickel and 5% Cobalt. This combination is extremely useful for the deposition of carbon materials (Nanotubes/diamond etc.) in plasma. I flattened out and cleaned these metal sheets and cut them into 1×1 square cm. substrates. Then I exposed these substrates to a hexane plasma in an Electron Cyclotron Resonance Plasma reactor and got wonderful nanodiamond deposition. My advisor and I were very excited on this and published this research in the Journal of Physics D : Applied Physics. This was a prime example that research is everywhere and just needs to be discovered!
4) You have studied a variety of plasma systems: DBD, ECR, etc. In your opinion, what are the “hottest” topics currently in the plasma field?
In my opinion, the most significant topic in the plasma field today is that of space propulsion. The Variable Specific Impulse Magnetoplasma Rocket, or VASIMR, is the engine that promises to use plasma technology to generate plasma. This engine will generate plasma by ionizing pressurized gases using radio waves. The resulting plasma will be controlled using magnetic fields. This 123,000 mph plasma engine could finally take astronauts to Mars in just a matter of 39 days. To use the full potential of a plasma, pressure has to be decreased which makes space the ideal scenario. I believe it would eventually be the advancement in plasma technology which will solve glaring problems faced by mankind such as energy and travel.
5) Do you keep in touch and continue to mentor your former students?
Yes, I keep in touch with my previous students and help them make crucial decisions where they might need my advice. I believe that students are a former version of yourself, maybe 10-15 years ago and will be tackling similar challenges that you faced. So, even after the students leave the institute and go into their respective careers, they must have someone to mentor them when they require help.
6) Describe some of the professional challenges that you are currently facing and hope to overcome in the next few years?
I faced a big professional & personal change when I decided to move to the US for family reasons. Finding a permanent position is one of the current challenges I am facing at the moment. I am working with a startup firm with which we are developing a new instrument and hope to launch it in the market soon. For this purpose, obtaining funding is another challenge. Having already gained technical expertise in my field, it is quite a refreshing experience to learn about the intricacies of obtaining funds and setting up a technology based business in a foreign land (US).