Initially he worked on accelerator theory. Later, he took up the challenge of technology development and built up a group that has indigenously developed a Plane-Wave Transformer linac and undulators for the free-electron lasers, and are working on photoinjectors for short wavelength FELs.
Dr. Krishnagopal was awarded the N.S. Sathyamurthy Young Scientist Award of the Indian Physics Association in 1996; he was elected Member of the National Academy of Sciences, Allahabad, India, in 1998; he was awarded the Outstanding Research Investigator Award of the Science Research Council of the Department of Atomic Energy in 2005; and in 2022 he was elected Fellow of the American Physical Society