In 1947, Prokhorov started working on coherent radiation emitted by electrons orbiting in a cyclic
particle accelerator called a
synchrotron. He demonstrated that the emission is mostly concentrated in the
microwave spectral range. His results became the basis of his
doctoral (
Dr. Sc.) thesis titled
Coherent Radiation of Electrons in the Synchrotron Accelerator, defended in 1951. By 1950, Prokhorov was assistant chief of the oscillation laboratory. Around that time, he formed a group of young scientists to work on radiospectroscopy of molecular rotations and vibrations, and later on
quantum electronics. The group focused on a special class of molecules which have three (non-degenerate) moments of inertia. The research was conducted both on experiment and theory. In 1954, Prokhorov became head of the laboratory. Together with
Nikolay Basov he developed theoretical grounds for creation of a
molecular oscillator and constructed such a device based on
ammonia. They also proposed a method for the production of population inversion using inhomogeneous electric and magnetic fields. Their results were first presented at a national conference in 1952, but not published until 1954–1955. In 1957, while studying
ruby, a
chromium-doped variation of aluminium oxide, he came upon the idea of using this material as an active medium of a
laser. As a new type of laser resonator, he proposed, in 1958, an "open type" cavity design, which is widely used today. In 1963, together with A. S. Selivanenko, he suggested a laser using two-quantum transitions. For his pioneering work on lasers and masers, in 1964, he received the
Nobel Prize in Physics shared with
Nikolay Basov and
Charles Hard Townes. == Posts and awards ==