Answer
Yes, Aleksandr Prokhorov completed his research primarily in the 20th century. Prokhorov was a Soviet physicist and inventor who is best known for his work on masers and lasers. He shared the Nobel Prize in Physics in 1964 with Charles Townes and Nikolai Basov for their work on masers. Prokhorov's research in the 20th century helped to lay the foundation for the development of modern lasers and other optical devices.