A versatile theoretical physicist, Ahmad made significant contributions in the theoretical development of the applications and concepts involving the particle physics, and its relative extension to the quantum electrodynamics, while working as senior research scientist at the CERN in 1960s and 1970s. Joining the PAEC in late 1950s, Ahmad served as the director of the Nuclear Physics Division at the secret Pinstech Institute which developed the first designs of atomic bombs, a clandestine project during the post-1971 war. There, he played an influential role in leading the physics and mathematical calculations in the critical mass of the weapons, and did theoretical work on the implosion method used in the weapons.