Radhakrishnan Nagarajan earned his BSc (Hons) (Physics) from Delhi University. After completing the Training School Program (1964) of Bhabha Atomic Research Centre (BARC), Mumbai, he joined Tata Institute of Fundamental Research (TIFR), Mumbai and carried out research in solid state physics using Mossbauer spectroscopy. He retired from there in 2004 as Professor in the Department of Condensed Matter Physics and Materials Science. Presently, he is Adjunct Professor at the Centre of Excellence for Basic Sciences of the Mumbai University and the Department of Atomic Energy.
Academic and Research Achievements: Nagarajan developed data acquisition systems for Mossbauer spectroscopy which were adopted by many groups in India. In collaboration with his colleagues, he investigated the valence fluctuation behaviour of Europium ion in several Europium-based intermetallics, using Europium Mossbauer spectroscopy which has been well recognized internationally. In 1993, he and his colleagues discovered superconductivity in yttrium-nickel-boron-carbon alloy (Tc ~15 K), the first system to exhibit superconductivity in a quaternary (four element) system. The discovery led to several new superconductors having transition temperature greater than 10 K, and some of them exhibiting the exotic phenomenon of coexistence of superconductivity with magnetism. The magnetic superconductors had interesting properties, which made them model materials for investigation of the phenomenon and leading to a new area of research 'superconductivity and magnetism in quaternary borocarbides'. He has nearly 200 publications to his credit in peer reviewed journals.
Other Contributions: As Chairman, Low Temperature Facility at TIFR, Professor Nagarajan provided dynamic leadership for enhanced research activity at liquid helium temperatures (4.2 K and below).
Awards and Honours: Nagarajan was conferred many recognitions, notably the Materials Prize by INSA (2003), Medal of the Materials Research Society of India, and Professor R Srinivasan Award for Low Temperature Physics/Cryogenics of Inter-University Consortium for Department of Atomic Energy Facilities. He was elected Fellow of the Indian Academy of Sciences, Bangalore and the National Academy of Sciences (India), Allahabad.