The Specific Heat of a Free-Electron gas calculated by using the Fermi

AI Thread Summary
The discussion focuses on calculating the specific heat of a free-electron gas in potassium using the Fermi energy. The equation for specific heat, C_v, involves the density of states at the Fermi energy, g(ε_f), which is challenging to determine without knowing the Fermi energy, E_f, or the temperature, T. Participants express difficulty in calculating g(ε_f) due to missing values for E_f and the appropriate temperature, questioning whether T can be arbitrarily chosen. The complexity of measuring the electron-specific heat is also highlighted, suggesting inherent challenges in experimental setups. Resources are recommended for further understanding of the topic.
nboogerz
Messages
4
Reaction score
0

Homework Statement



Here g(ε_f) is the density of levels at the Fermi energy and T is the temperature. Calculate the specific heat of the electron gas in potassium (K) treating it as a free gas. For a free gas the density of electrons at ε_f is: g(ε_f)=(3/2)(n/E_f) where n is the electron density in the gas. Why is the contribution of the electron specific heat so hard to measure?

Homework Equations



C_v=(1/3)(∏^2)(k_B)^2Tg(ε_f)

The Attempt at a Solution



Okay I'm taking n to be the total number of electrons in potassium(19) I still can't calculate a value for g(ε_f) as I still don't know what to put in for E_f as its not given in the problem. Also I'm not sure what to put in for T. Can I take this as another arbitary value as putting 0K for the temperature at the fermi level causes the equation to collapse.
 
Physics news on Phys.org
nboogerz said:

Homework Statement



Here g(ε_f) is the density of levels at the Fermi energy and T is the temperature. Calculate the specific heat of the electron gas in potassium (K) treating it as a free gas. For a free gas the density of electrons at ε_f is: g(ε_f)=(3/2)(n/E_f) where n is the electron density in the gas. Why is the contribution of the electron specific heat so hard to measure?

Homework Equations



C_v=(1/3)(∏^2)(k_B)^2Tg(ε_f)

The Attempt at a Solution



Okay I'm taking n to be the total number of electrons in potassium(19) I still can't calculate a value for g(ε_f) as I still don't know what to put in for E_f as its not given in the problem. Also I'm not sure what to put in for T. Can I take this as another arbitary value as putting 0K for the temperature at the fermi level causes the equation to collapse.

It would be better if you consult from these sites:

http://www.cmmp.ucl.ac.uk/~ikr/3225/Section 6.pdf
http://www2.binghamton.edu/physics/docs/note-free-electron-gas.pdf
http://www.theo3.physik.uni-stuttgart.de/lehre/ss08/sst/Script-AHCN-Chap-6.pdf
http://phy.ntnu.edu.tw/~changmc/Teach/SS/SSG_note/mchap06.pdf
http://www2.binghamton.edu/physics/docs/note-free-electron-gas.pdf
 


I'll have a look at them thanks.
 
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Struggling to make relation between elastic force and height'
Hello guys this is what I tried so far. I used the UTS to calculate the force it needs when the rope tears. My idea was to make a relationship/ function that would give me the force depending on height. Yeah i couldnt find a way to solve it. I also thought about how I could use hooks law (how it was given to me in my script) with the thought of instead of having two part of a rope id have one singular rope from the middle to the top where I could find the difference in height. But the...
Back
Top