Known for his research on the thermal and transport behaviour of magnetic systems, Sampathkumaran is an elected fellow of all the three major Indian science academies viz. Indian Academy of Sciences, Indian National Science Academy and National Academy of Sciences, India as well as The World Academy of Sciences. The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards, for his contributions to physical sciences in 1999.