The wavelength of a 2 eV photon is given by:
where the photon energy was multiplied with the electronic charge to convert the energy in Joule rather than electron Volt.
The kinetic energy of an electron is related to its momentum by:
from which we find the momentum,
p:
The de Broglie wavelength of the electron is then obtained from:
- l = h c / Eph = 6.625 x 10-34 x 3 x 108/(1.6 x 10-19 x 2) = 621 nm.
T = p2/2m
p = (2mT)1/2 = (2 x 9.1 x 10-31 x 1.6 x 10-19 x 2)1/2 = 7.63 x 10-25 kg m/s.
l = h/p = 6.625 x 10-34 / 7.63 x 10-25 = 0.87 nm
