- #1
azaharak
- 152
- 0
Hi
Got a question, hoping someone can give a good explanation for.
We all know that large static uniform electric fields have the potential to ionize. (Dielectric breakdown of Air - Static Electricity Shock).
In the Quantum picture, why does this occur. Take for instance the photo electric effect, increasing the intensity of radiation does not allow for electron ejection/excitation unless the frequency is above a certain threshold.
The frequency for a static field, I'm assuming to be zero. I'm thinking that, (virtual photons) could play a role in the underlying static field, and these photons might be the right frequency to ionize?
For a large static field, I understand why the ionization occurs classically but ...
I understand that a large enough static field, can liberate the electron classically.
I understand that even without this large static field that tunneling is a possibility.
What I don't understand is how a static field is really that much different from extremely low frequency radiation.
What I have learned is that only certain frequencies of radiation (light) can produce excitation or ionization. Increasing the intensity of a non resonant frequency will not liberate the electron (here the frequency is less that than threshold Like photo electric effect).
For instance, take really large intensity radiowaves Such that they will produce a huge electric field that is time varying. But they should not be able to ionize an atom?
Is the difference here that large intensities are many single photon combination.
What is so different between a high intensity static electric field and high intensity extremely low frequency radiation, other than the magnetic field tagging along with the radiation and the sinusoidal dependence?
Still a little uncertain.
Thank you all for your responses.
Best
Az
Got a question, hoping someone can give a good explanation for.
We all know that large static uniform electric fields have the potential to ionize. (Dielectric breakdown of Air - Static Electricity Shock).
In the Quantum picture, why does this occur. Take for instance the photo electric effect, increasing the intensity of radiation does not allow for electron ejection/excitation unless the frequency is above a certain threshold.
The frequency for a static field, I'm assuming to be zero. I'm thinking that, (virtual photons) could play a role in the underlying static field, and these photons might be the right frequency to ionize?
For a large static field, I understand why the ionization occurs classically but ...
I understand that a large enough static field, can liberate the electron classically.
I understand that even without this large static field that tunneling is a possibility.
What I don't understand is how a static field is really that much different from extremely low frequency radiation.
What I have learned is that only certain frequencies of radiation (light) can produce excitation or ionization. Increasing the intensity of a non resonant frequency will not liberate the electron (here the frequency is less that than threshold Like photo electric effect).
For instance, take really large intensity radiowaves Such that they will produce a huge electric field that is time varying. But they should not be able to ionize an atom?
Is the difference here that large intensities are many single photon combination.
What is so different between a high intensity static electric field and high intensity extremely low frequency radiation, other than the magnetic field tagging along with the radiation and the sinusoidal dependence?
Still a little uncertain.
Thank you all for your responses.
Best
Az