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Quantum Behavior of Electrons

  1. Jul 28, 2011 #1
    For a simple network of resistive circuit, we can compute the values of current and voltages right? However, I'm more curious about how each individual component behave. Is it possible to somehow isolate each resistor and compute their values individually (e.g. not having to compute the entire network first but through step-by-step, one component at a time, being able to compute the desired quantity, the bottom-up approach.) If so, how can this be done. Will the continuity equation in a closed system possibly give a solution? More exactly, how does electrons behave during their propagation through a material (in this case, a resistor, for simplicity).
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  3. Jul 28, 2011 #2


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    I really don't understand what you are asking, or what it has to do with quantum mechanics (which isn't even mentioned in your post). What values do you want to compute for each individual component? Are the components connected in an electrical circuit? Is current flowing?

    Anyway, if you are asking about whether or not the quantum behavior of electrons flowing through bulk conductors can be accounted for, then answer is yes. There are many ways of doing this, starting from the Drude model, where the metal is treated as a lattice of positively charged ions and the detached electrons in the conductor are modeled as an "electron gas". There are many subsequent refinements of this general idea, but it is a good place to start.
  4. Jul 28, 2011 #3
    Thanks for the reply. Regarding the values I'm interested to get, it's the current and the voltage for each individual component, and if possible the heat emission. Current is assumed to be flowing. Regarding the "electron gas" model, does this mean that if I will treat electrons as gas particles then I can relate values like voltage to pressure and current to rate of flow? How do I model this?
  5. Jul 28, 2011 #4


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    You may not have realized that there's a branch of physics known as solid state physics/condensed matter physics that deals with the behavior of materials.

    If you want resources on how physics/quantum mechanics treat charge transport in metals, then an intro text in solid state physics (such as Kittel's) might be useful. Also, a search on the Drude model (which is semi-classical at best) might give you some insight into how quantity such as resistivity is derived.

  6. Jul 28, 2011 #5
    Thank you for replying, it is true that I have not realized the branch of physics: solid state physics during my course (thanks to my very industrious professor :grumpy:), that's why I'm left researching other stuffs myself. Can you recommend a good book about the subject. Also, which topic should I study under this branch?

    Thanks again :smile:
  7. Jul 29, 2011 #6
  8. Jul 29, 2011 #7
    To everyone, thank you for your reply. This will help me a lot!
  9. Jul 29, 2011 #8
    Although I don't know the details, I would think the ease with with a material conducts electricity is closely related to the binding energy of the outer orbital electrons....the conducting electrons. So you can think conceptually of current flowing easily in a material where outer electrons are loosley tied to each atom (typically they would be called conducting electrons) and resistors have electrons which are tightly bound...meaning it takes a lot of applied potential to overcome the electrons attraction to it's local nucleus.

    In semiconductors, the theory of holes (positive carriers) also plays a big role. The theory of current and voltage in semicinductors is well established...I can still remember the agony of plowing through semiconductor current equations in graduate school....bottom up estimates, for example, where amplification in a transistor would be approximately linear....

    and that was a long time ago...besides the suggestions above, consider looking in a text of transistor or semiconductor theory...for an electrical engineering curriculum.
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