Register to reply 
Fermi Energy of Liquid He3 
Share this thread: 
#1
Feb1912, 04:42 PM

P: 196

1. The problem statement, all variables and given/known data
The atom [itex]He^3[/itex] has spin 1/2 and is a fermion. The density of liquid [itex]He^3[/itex] is [itex]0.081g/cm^3[/itex] near absolute zero. Calculate the Fermi energy [itex]\epsilon_F[/itex] and the Fermi temperature [itex]T_F[/itex] 2. Relevant equations [itex]\epsilon_F = \frac{\hbar^2}{2m}(\frac{3 \pi^2 N}{V})^{2/3}[/itex] [itex]T_F = \frac{\epsilon_F}{k}[/itex] 3. The attempt at a solution In the problem I'm given the density is [itex]0.081g/cm^3[/itex], which is my N/V. Assuming that m is the mass of [itex]He^3[/itex], then [itex]m = 5.008*10^{24}g[/itex]. I should then be able to do a straight forward plugnchug; however my units don't work out as I get: [itex]\epsilon_F = \frac{\hbar^2}{1.0016*10^{23}g}(3 \pi^2 0.081g cm^{3})^{2/3}=1.99*10^{50} kg^{5/3} m^2 s^{2}[/itex] Clearly, this is not a unit of energy. What am I doing wrong? 


#2
Feb1912, 08:25 PM

P: 196

I need to use number density, rather than straight density. Which should take care of my problem.



Register to reply 
Related Discussions  
Fermi energy and ratio of the number of occupied levels at an energy  Advanced Physics Homework  5  
Fermi energy and quasiFermi energies in pnjunctions  Atomic, Solid State, Comp. Physics  0  
Band structure and fermi liquid  Atomic, Solid State, Comp. Physics  1  
About Fermi energy and Fermi temperature  Atomic, Solid State, Comp. Physics  6  
Fermi Gas Model / Fermi energy and momentum  High Energy, Nuclear, Particle Physics  1 