Ajit Ram Verma did his BSc (1940) and MSc (1942) from the University of Allahabad. After working for a short period as Research Scholar at Allahabad, he joined University of Delhi as Lecturer in Physics (1947). During 1950-55, he worked at the University of London and made well-known contributions on the observation and study of unimolecular growth spirals on the surfaces of silicon carbide crystals. He was awarded PhD (1952) and DSc (1969) by the University of London. He worked as Reader in Physics, University of Delhi (1955-59); Professor and Head, Department of Physics, Banaras Hindu University (BHU) (1959-65); and Director, National Physical Laboratory (NPL), New Delhi (1965-82). Thereafter, he was Visiting Professor at IIT Delhi, Jawaharlal Nehru Fellow, CSIR Emeritus Scientist and INSA Senior Scientist at NPL.
Academic and Research Achievements: Dr Verma established three very active schools of research in crystallography at Delhi University, BHU and NPL. While working at the University of London in 1951, using Phase Contrast Microscopy, he directly observed unimolecular growth spirals on the surfaces of silicon carbide crystals of millimetric sizes and measured their step heights of 15 Å by using multiple beam interferometry and showed them equal to the X-ray unit cell size. This was the first unequivocal support of the screw dislocation theory of crystal growth. This work showed the power of phase contrast microscopy. The correlation of the step heights of growth spirals with the dimensions of X-ray unit cell had helped in explaining the phenomenon of polytypism by the screw dislocation theory propounded by FC Frank. He made pioneering research on direct measurement of metric thicknesses of Blodgett-Langmuir molecular films. At NPL, in collaboration with Krishan Lal, several important contributions were made in the field of crystal growth and study of lattice imperfections. These include: (i) investigation of growth and defects in whisker crystals showing absence of axial screw dislocations in these crystals; (ii) establishing an X-ray diffraction topography facility for investigation of single crystals of technologically important crystals; (iii) systematic studies of high resolution diffuse X-ray scattering showing that at and near the room temperatures, diffuse scattering is primarily due to defects and not due to thermal vibrations of the lattice; and (iv) establishing presence of a forward direct beam in the case of ‘thin’ diamond crystals of varying degree of perfection. Study of zeroth order diffraction from single crystals was also pursued. He has authored six books/volumes and published more than 100 research papers in refereed journals. Two of his books on crystal growth have been translated into Russian.
Other Contributions: As Director NPL Verma laid the foundation of several new areas of research. Under his leadership, NPL made strong impact at the national and international levels. He served as Charter Member of the Board of Editors of Solid State Communications (Pergamon Press), Member of International Committee on Weights and Measures, Paris (1966-82), and Member, Commission on Symbols, Units and Nomenclature of the International Union of Pure & Applied Physics.
Awards and Honours: Dr Verma received the SS Bhatnagar Prize in Physics (1964), Padma Bhushan (1982), Atma Ram Puraskar by Kendriya Sansthan, Agra (1984), British Council Scholarship (1950-52) and ICI Fellowship (1952-55). He was elected Fellow of the Indian Academy of Sciences, Bangalore and National Academy of Sciences (India), Allahabad.