- (Honorary Faculty Fellow of the Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore since 2006)
- Scientist (July, 1994 –to-date) at the Photosciences and Photonics Group, National Institute for Interdisciplinary Science & Technology, Trivandrum, India.
- Junior Research Fellow (1985-1987) and Senior Research Fellow (1987-1989) of the Council ofScientific and Industrial Research, (with Late Professor K. Saramma, Department of Chemistry,University of Kerala, Trivandrum, India).
- Research Associate (1989-1994) at the Photoscience and Photonics of the National Institute for Interdisciplinary Science & Technology, (CSIR), Trivandrum, 695 019 (with Professor M. V. George,Photosciences and Photonics, NIIST).
- Visiting Scientist, Radiation laboratory, University of Notre Dame, USA, Jan-Nov 1999; May-July 2003 and Aug-Sept 2004: Nov 2005. (Radiation laboratory, University of Notre Dame, Notre Dame, Indiana 46556 USA).