Prof. Shri Krishna Joshi (popularly known as Prof. S. K. Joshi) (6 June 1935-15 May 2020) was an Indian physicist. He was born in the village of Anarpa in Kumaun,UP (Now Uttarakhand), India. Dr. Joshi is an example of a person with hard work rising from a humble family background to the highest levels in the field of Science and Technology of India. Dr. Joshi studied at the Allahabad University and did his Ph.D. in Physics from there in 1962. His broad field of research interest is Condensed Matter Theory. He had earlier worked on Collision Processes in Atomic and Molecular Systems also.
Dr. Joshi was Professor of Physics at the University of Roorkee (Now IIT, Roorkee) from 1967 till 1986. He was the Director of National Physical Laboratory from 1986-1991. He held the position of the Director General CSIR from 1991 till 1995. After retiring in 1995, he was awarded the Sarabhai Research Professorship in Physics and worked on condensed matter theory at the National Physical Laboratory in New Delhi.
Prof. Joshi’s life journey from a small village of Uttarakhand to raising the position of Director General of Council for Scientific and Industrial Research, (DG, CSIR), New Delhi is motivational example for the aspiring youth of rural areas of the country that with their determination and hard work they can also achieve any position in science and technology fraternity. During his schooling days, he used to walk everyday several kilometers of tough terrains of Himalaya to reach his school. For his higher education, he moved to Allahabad University and obtained BSc and MSc (Physics) degrees, both with first class. In 1957, being the Gold medalist in MSc, he was offered the position of Lecturer in Physics at Allahabad University. In parallel, he started his research work in measurement of diffuse X-ray scattering from organic crystals for his doctoral degree with K Banerjee and received his PhD degree in 1962. In 1965 he was offered a position of Visiting Lecturer by University of California, Riverside, USA. After working two years in USA, he returned to India and joined as a Professor of Physics, at a pristine age of 32 years, at the University of Roorkee (now IIT Roorkee). His experimental work during his PhD and his experience in US, got him seriously interested in theoretical studies of lattice vibrations, i.e. phonons in metals and insulators. In metals, the frequencies of phonons depend on the response of conduction electrons to ion motion, and he proposed a successful phenomenological model incorporating electron response. He was one of the pioneers to understand the lattice dynamics of d-electron metals (e.g. copper and nickel) using a non-interacting s and d bands model. He investigated the electronic band structure using Korringa-Kohn-Rostoker method. The virtual crystal and the coherent potential approximation were used to calculate the electron states in a number of disordered binary alloys. He was one of the rarest Indian scientists who contributed a Chapter in Solid State Physics, published by Academic Press in 1968 on Lattice Dynamic of Metals, and other contributors in this book include Charles Kittle.
He also proposed a new variational method for the periodic Anderson model to study the ground state behavior of heavy fermions and estimated the c-axis resistivity of high temperature superconductors. NPL also started the work on nanotechnology. He investigated transport of electrons in mesoscopic systems, particularly, the conductance of a single quantum dot and a double quantum dot system. Apart from being an outstanding scientist, he was a visionary leader as well. Prof. S.K. Joshi was elevated to the position of Director General of CSIR and Secretary, DSIR, Government of India. It was the time that coincided with beginning of the economic liberalization in India and he successfully steered CSIR for the national scientific and technological needs. He served the nation in various ways. He played a crucial role in establishing new institutes of higher learning viz IISER, NISER, New IITs etc. He guided leading institutions of the country through the Chairmanship of their apex Boards, including IIT Roorkee, Institute of Mathematical Sciences, Chennai, Institute of Physics, Bhubaneswar, Indian Association for Cultivation of Science, Kolkata, Recruitment Assessment Center (RACDRDO), Recruitment Assessment Board(RAB CSIR), Visvesvaraya National Institute of Technology (VNIT Nagpur), Inter-University Accelerator Centre (IUAC), UGC-DAE, Indore etc. He also served as a member of the Scientific Advisory Committee to Government of India. He also served as Chairman of selection committees to select Directors and Vice Chancellors of many prestigious Institutes and Universities.
Research contributions: Dr Joshi’s major research contributions span over a wide variety of topics in solid state theory. His early researches were concerned mainly with theoretical study of phonons in metals and insulators. Dr Joshi studied electronic states in disordered systems and electron correlations in narrow band solids. He also worked on surface states and surface segregation. Latest research interest of Dr Joshi was related to strongly correlated electron systems like high temperature superconductors. He also worked in nanoscience, especially electron transport in quantum dots and nanotubes. Dr Joshi has supervised the Ph.D. thesis of 20 scholars and has published more than 190 research papers.
Academic recognitions: He received D.Sc (honoris causa) from Kumaon University in 1994, from Kanpur University in 1995, from Banaras Hindu University in 1996, from University of Burdwan in 2005 and from Bhimrao Ambedkar University (Agra University ) in 2008.
Prof. Joshi immensely contributed to Indian science and academies by serving at various positions. His passing is a great loss to the nation. His immense contributions to the Indian science and technology will always be remembered and will always act as guidelines for the growth of science and technology in the country with simple living and high thinking attributes. Professor S K Joshi has been known as one of the best science leader and condensed matter physicist of the country. In the last phase of his life, he was suffering from cancer in his thigh and was confined to bed but had his usual charismatic smile beneath which the deep pain of the illness was evident. Prof. S.K. Joshi was married to Hema, a gracious and charming lady, who during their 55 years of togetherness supported him in his personal (a strict follower of early to bed and early to rise) as well as professional (follower of simple living and high thinking)life. He leaves behind his wife and a son Sanjay, who is well settledat a high position inUSA with his family.