1. Photoelectric Effect (1)
Discovered in 1887:
Light can lead to the emission of electrons
from metal surfaces. Only the wavelength,
not the intensity of the light matters!
Heinrich Hertz
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2. Photoelectric Effect (2)
Nobel Prize for Physics (1921)
for explanation of the Photoelectric Effect:
Light energy is quantized (see Max Planck).
If the energy of a light quantum (photon) is
greater than the work function of a
given material, electrons will be emitted.
Albert Einstein
1879 – 1955
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3. Louis Victor Pierre Raymond,
Matter Waves
Louis Victor Pierre Raymond,
7e Duc de Broglie
( )
Nobel Prize for Physics, 1922
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