It’s impossible to imagine our world without the laser. It’s used everywhere: in medicine, telecommunications, industry and research. An important pioneer of laser technology was the physicist Charles Hard Townes, who died in Oakland, California, on January 27. He devoted his entire life to science and continued working long past retirement age.
We were fortunate to have had the chance to speak with Townes five years ago, in celebration of the laser’s 50th birthday. In fall 2010, he told Laser Community, “I conduct research, and that’s play, not work.” Read the entire interview here.
A life devoted to science
Charles Hard Townes was born on July 28, 1915 in Greenville, a small town in South Carolina. The son of a lawyer, Townes began studying physics at Furman University. After completing his bachelor’s degree, he went on to receive a master’s from Duke University in Durham, North Carolina, and in 1939 he earned his Ph.D. in Physics from the California Institute of Technology in Pasadena, near Los Angeles. His dissertation was on isotopes and nuclear spin. During the Second World War, he developed radar systems for Bell Telephone Laboratories in New York and New Jersey. During his time there, Townes started working with microwave technology for the first time – an important milestone on the way to his most important invention.
Invention on a park bench
In 1948, Townes was appointed to the physics faculty at Columbia University in New York City, where he continued his research on microwave physics and studied the interactions between microwaves and molecules. Early one morning in April 1951, while sitting on a park bench in Franklin Park in Washington, D.C., Townes had a brainstorm related to his most important invention. In his memoirs, Townes describes sitting under blooming azaleas and writing on the back of an envelope the decisive idea for how to systematically intensify microwaves.
Three years after this eureka moment, Townes presented an apparatus that could generate and intensify microwaves. He called it a “maser,” short for microwave amplification by simulated emission of radiation. Working with his brother-in-law Arthur Schawlow, in 1958 Townes developed the idea that this method could also be used for intensifying light.
Even so, the concept remained theoretical. The world’s first functional laser was actually built by someone else. Theodore H. Maiman and his team generated the first laser beam using a ruby laser in a California lab on May 16, 1960. Still, Townes was recognized for his groundbreaking work in this area when he received the Nobel Prize in Physics in 1964.
From lasers to the stars
By this point, Townes had already turned to another field: astronomy. He and his colleagues were the first to detect complex molecules in interstellar space and measure a black hole in the middle of the Milky Way – with help from maser and laser technology, of course. He also served on various government commissions; from 1966 to 1970, for example, he chaired the NASA Science Advisory Committee for manned space flight.
Even after emeritus status was conferred upon him in 1984, Townes did not stop conducting research. Right up until the very end, he continued to go to his office each day at the University of California – Berkeley where he had been a professor since 1967. Townes would have turned 100 years old on July 28, 2015.