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sinayu71
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can someone simply describe the definition of the chemical potential?
Well, I am not in a high level of education especially in physics. Like you say, I may find it in my lecture note, so, it won't be so hard for you just make a few lines to tell me the definition of it. Particularly, I am curious to know that how do you interpret the chemical potential in the semiconductor material?Welcome to the forums sinayu71,
If you would permit me, could I ask what your level of education is? Why do you need to know it and why isn't it in your lecture notes?
I'm confused by your post. Chemical potential is not the same as energy, so what are the enthalpy and entropy contributions to chemical potential? What role do they play in semiconductors, which is what the original poster asked about?The enthalpy contribution (in the mixing and pure component terms) to Chemical Potential is easy to define. What is really hard to define for Chemical Potential is the Entropy contribution. Entropy is one of the hardest quantities to define in the physical sciences today. Most physics people will tell you that entropy is a measure of the "randomness" of the system, but that is a purely statistical approach which clouds our true understanding of this important quantity. Hope this helps.
Best Regards
Modey3
Actually the chemical potential can be defined in terms of the total internal energy, the Helmholtz free energy or the Gibbs free energy, depending on what quantities are held constant.Well unless there are two definitions of chemical potential it is defined in only one way. Any book on thermodynamics defines chemical potential as the Gibbs Free Energy change per atom (or mole) at constant Temperature and Pressure.
How does this help explain, in a simple way, the Fermi level of a bulk semiconductor?Since Gibbs Free Energy is a function of enthalpy and entropy chemical potential must also be a function enthalpy (H) and entropy (S). H and S can then be broken down into their pure material and mixing contributions.