*Thomas Young's double-slit experiment demonstrating the wave nature of light. (c. 1801)
*Henri Becquerel discovers radioactivity. (1896)
*J. J. Thomson's cathode ray tube experiments (discovers the electron and its negative charge). (1897)
*The study of black-body radiation between 1850 and 1900, which could not be explained without quantum concepts.
*The photoelectric effect: Einstein explained this in 1905 (and later received a Nobel prize for it) using the concept of photons, particles of light with quantized energy.
*Robert Millikans oil-drop experiment, which showed that electric charge occurs as quanta' (whole units). (1909)
*Ernest Rutherford's gold foil experiment disproved the plum pudding model of the atom which suggested that the mass and positive charge of the atom are almost uniformly distributed. This led to the planetary model of the atom (1911).
*James Franck and Gustav Hertz's electron collision experiment shows that energy absorption by mercury atoms is quantized. (1914)
*Otto Stern and Walther Gerlach conduct the Stern–Gerlach experiment, which demonstrates the quantized nature of particle spin. (1920)
*Arthur Compton with Compton scattering experiment (1923)
*Clinton Davisson and Lester Germer demonstrate the wave nature of the electron in the electron diffraction experiment. (1927)
*Carl David Anderson with the discovery positron (1932), validated Paul Dirac's theoretical prediction of this particle (1928)
*Lamb–Retherford experiment discovered Lamb shift (1947), which led to the development of quantum electrodynamics.
*Clyde L. Cowan and Frederick Reines confirm the existence of the neutrino in the neutrino experiment. (1955)
*Clauss Jönsson's double-slit experiment with electrons. (1961)
*The quantum Hall effect, discovered in 1980 by Klaus von Klitzing. The quantized version of the Hall effect has allowed for the definition of a new practical standard for electrical resistance and for an extremely precise independent determination of the fine-structure constant.
*The experimental verification of quantum entanglement by John Clauser and Stuart Freedman. (1972)
*The Mach–Zehnder interferometer experiment conducted by Paul Kwiat, Harold Wienfurter, Thomas Herzog, Anton Zeilinger, and Mark Kasevich, providing experimental verification of the Elitzur–Vaidman bomb tester, proving interaction-free measurement is possible. (1994)