Schrödinger's discovery of coherent states

Abstract

Already in 1926, Schrödinger constructed “minimum uncertainty wave packets” for the harmonic oscillator, later popularized as “coherent states”, which today are widely used, for instance in quantum optics (laser theory) and in quantum field theory (infrared behaviour in QED and QCD). It is argued that Schrödinger's discovery of coherent states played a crucial role in Heisenberg's discovery of the uncertainty principle in 1927.