"We should note that this latter type of shift was successfully amplified to a considerable extent by Russian physicists using the intense light of a ruby laser whose wavelength is close to that of a transition of the potassium atom."
Alfred Kastler was a French physicist who received the 1966 Nobel Prize in Physics. He is known for developing optical pumping techniques that became foundational in atomic physics. He was born on May 3, 1902, and died on January 7, 1984.