This document discusses the history of phonons in physics from their conceptualization by Russian physicists Y. Frenkel and Tamm to their experimental observation using triple axis spectrometers invented by Canadian physicist B. N. Brockhouse at nuclear reactors in Chalk River, Ontario, for which Brockhouse won the 1994 Nobel Prize.

1. Phonons: concept and/or reality?
Y. Frenkel, Russian Physicist
1894-1952
Tamm, Russian Physicist
1895-1971
1958 Nobel Laurate

3. Meanwhile at Chalk River
NRX Reactor
NRU Reactor

4. Invention of the Triple Axis Spectrometer
B. N. Brockhouse 1957
Nobel Prize 1994