Reflections on
the First Maser
James P. Gordon
Before the laser, there was the maser, and, before that, an idea: to
build a microwave amplifier using ammonia molecules. Here, Jim
Gordon takes us back to the early 1950s, when he had to decide
whether Charles Townes’s vision for creating a coherent oscillator
was promising enough for him to commit to for his Ph.D. project.
AIP Emilio Segre Visual Archives, Physics Today Collection
n April 1954, when five of us were having lunch in the Columbia teacher’s college caf-
eteria, Charles Townes proposed that we name the coherent oscillator that we had just
created. He vetoed any name that ended in “-tron.” Before we left, we had created the
name maser, an acronym for “microwave amplification by stimulated emission of radiation.”
Before long, Arthur Schawlow had re-imagined the maser acronym to mean “money acquisi-
tion schemes for expensive research.” Back then, none of us could have imagined how critical
the maser would be in shaping optical technology in the 20th century and beyond. These are
my recollections of how the maser came to be.
I
How it all began
Sometime in mid-1951, I got a call from Professor Townes asking if I would care to join
him on a project he had in mind—to build a coherent molecular oscillator. I had come
to the Columbia Graduate School of Arts and Sciences after graduating from MIT in
1949 with a B.S. in physics. (I had also applied for graduate studies at MIT, but I was not
May 2010 | 35
1047-6938/10/05/0034/8-$15.00 ©OSA
