Electron frequency and wavelength

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SUMMARY

The discussion centers on the wave nature of electrons, specifically the relationship between frequency and wavelength. The de Broglie wavelength of an electron is defined as λ = h/p, where h is Planck's constant and p is momentum. The frequency of an electron is related to its energy through the equation f = E/h, contrasting with the photon relationship f = c/λ. The confusion arises from the distinction between phase velocity and group velocity, which are critical in understanding the behavior of massive particles like electrons.

PREREQUISITES
  • Understanding of de Broglie wavelength and its formula (λ = h/p).
  • Knowledge of the relationship between energy and frequency (E = hf).
  • Familiarity with phase velocity and group velocity concepts.
  • Basic principles of quantum mechanics and particle-wave duality.
NEXT STEPS
  • Study the derivation of the de Broglie wavelength for various particles.
  • Learn about phase velocity vs. group velocity in quantum mechanics.
  • Explore the implications of the wave-particle duality on electron behavior.
  • Investigate experimental confirmations of de Broglie's hypothesis.
USEFUL FOR

Students of quantum mechanics, physicists exploring wave-particle duality, and educators seeking to clarify the concepts of electron behavior in wave theory.

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Hi, I'm studying the wave nature of particles.

My book says that the de broglie wavelength of an electron is h / momentum, or h / (mv).
I also have that E = hf = momentum2/(2m) = 1/2 mv2.
I know that for a photon the frequency is speed of light / wavelength.


I'm wondering why the frequency for an electron is not 1/ wavelength. Is there any equation relating f and lambda for a particle (electron)?

Thanks for any help.
 
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DeBroglie predicted the wavelength of matter waves would be the same as for the photon.
The releatonship you want is the one you stated: f = c/lambda

Experimental confirmation is discussed here:
http://en.wikipedia.org/wiki/DeBroglie_wavelength
 
Naty's answer seems very wrong to me. The wavelength of a particle is tied to its momentum. The frequency is related to its energy. When you combine the wavelength and frequency to get the apparent velocity of the electron, the answer comes out wrong. You don't get the correct velocity.

The resolution of this paradox comes from a careful analysis of the roles of phase velocity vs. group velocity.
 
Naty1 said:
The releatonship you want is the one you stated: f = c/lambda

If c is the speed of light, that works only for photons.

For particles with mass, f = v_{phase} / \lambda which gives

v_{phase} = f \lambda = \left( \frac{E}{h} \right) \left( \frac{h}{p} \right)<br /> = \frac{E}{p} = \frac {\sqrt{(pc)^2 + (m_0 c^2)^2}}{p}
 
Duh, seems wrong to me, too; right your guys are!..I should have posted f = E/h
the equations are right there in the wiki reference, too.
 

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