de Broglie Wavelength
de Broglie wavelength, or Compton wavelength is the wavelength of particles in their wave nature.
\(\lambda=h/p\)
For composite particles, the wavelength is the resultant of diffraction of wavelengths, but then the condition for it is that all the individual waves diffracting should be in phase, or be "coherent".
The largest object for which the diffraction was experimentally observed was the \(C_{60}\) molecule, or Buckminster Fullerene. But quantum decoherence was very strong in this experiment, and the theoretical wavelength could only be obtained by including it.
Simulation of matter waves in Bohr's Model