After finishing his Ph.D. at IIT,Delhi, Kaw went to Princeton University, USA first as a postdoc. and later as an Asstt. Professor. During this period (1967-71) he made seminal contributions to nonlinear problems connected with laser - plasma interactions. Notable among these works are: (a) laser induced parametric instabilities which lead to anomalously large absorption as well as back and side-scattering; (b) filamentation of laser light due to ponderomotive forces in a plasma and (c) relativistic nonlinear effects which have also found application in pulsar radiation phenomena. Most of these results have received confirmation by subsequent experiments and computer simulations.

From 1971-75, Kaw was back in India as Associate Professor and Professor at the Physical Research Laboratory, Ahmedabad. In this period he extended the theory of parametric instabilities to magnetized plasmas. His review articles written in this period are widely used and have had significant impact on development of intense RF heating in magnetized plasmas and interpretation of ionospheric heating experiments at Arecibo. He also made important contributions to the theory of ionospheric irregularities in the equatorial electrojet.

In 1975 Kaw returned to Princeton University with the rank of a Professor and initiated work on magnetically confined fusion plasmas. He made three pioneering contributions in this period (1975-82). (a) He showed that decades old conventional wisdom on the stability of drift waves in sheared geometry (a prime candidate for transport in fusion devices) was incorrect. (b) He demonstrated the existence of coalescence instability of magnetic islands and showed how model calculations can elucidate complex nonlinear magnetic reconnection phenomena (these ideas have found applications in diverse phenomena like disruption in tokamaks, energy release in solar flares and sub-storm effects in tail regions of magnetosphere). (c) He developed a novel passive approach to current drive in reactor grade plasmas using synchrotron radiation emitted by such plasmas naturally - a technique which is widely regarded as the basis for future advanced fuel reactors.

In early eighties Kaw and some of his former colleagues at PRL succeeded in persuading the Deptt. of Science and Technology, Govt. of India, to set up a major programme of plasma physics at PRL. He returned to India in 1982 to direct this programme. The programme was separated from PRL in 1986 and became the DST funded Institute for Plasma Research. In 1996, the IPR was taken over by the Deptt. of Atomic Energy with a considerable upscaling of the experimental efforts on thermonuclear fusion. The major achievements of the Institute in the past two decades have been fivefold: (i) A medium sized tokamak reactor called ADITYA was indigenously designed and fabricated. This machine was commissioned in 1989 and has led to some very novel results on intermittency in tokamak edge turbulence. (ii) A large number of basic experiments investigating fundamental processes in plasmas have been set up and have led to exciting new physics. (iii) The Institute has successfully developed a number of plasma processing technologies like plasma nitriding, zircon sand benefication, SiO2 coating, plasma ion implantation, plasma pyrolysis for medical waste disposal etc. and some of these technologies have been transferred to Indian industries. (iv) The Institute has carried out the design/fabrication of an advanced steady-state superconducting tokamak SST-1. This machine is undergoing commissioning trials now and is one of the first machines of this kind anywhere in the world. (v) The Institute successfully spearheaded India’s case for participation in the prestigious ITER experiment and is now the nodal domestic agency looking after this participation.

His personal research in this period (1986-08) may be classified under three categories. In tokamak research, he and his colleagues have pioneered the research on intermittency in tokamak edge plasmas. They have also made important contributions to theory of MARFE and other radiation driven instabilities. The second category of papers deals with novel properties of exotic plasmas. He has done pioneering work on (a) non-perturbative effects in classical quark-gluon plasmas, (b) toroidal equilibrium of non-neutral electron clouds and (c) collective effects in dusty plasmas. Lastly he has continued his investigations on nonlinear phenomena in relativistic light plasma interactions. Here he has made important contributions to theory of envelope solitons and to the physics of anomalous stopping of fast electrons, a topic of great interest to fast ignition concept of laser fusion.