Title 



Imperfect fermi gas : kinetic and interaction energies
 
Author 


  
Abstract 



A uniform groundstate threedimensional Fermi gas with shortrange repulsive pairwise interaction is under consideration. Its kinetic and interaction energies are calculated up to the second order of the expansion in the gas parameter. Similar to recent results for an interacting Bose gas, the quantities in question are found to depend on the pairwise interaction through two characteristic lengths: the former, a, is the swave scattering length, and the latter, b, is related to a by b=am(partial derivativea/partial derivativem), where m stands for the fermion mass. To control the results, we proceed in two independent ways. The first involves the HellmannFeynman theorem applied to derive the kinetic and interaction energies from the totalenergy expansion in the gas parameter first found by Huang and Yang. The second way operates with inmedium pair wave functions and allows one to calculate the quantities of interest "from scratch." The results of the present investigation, taken together with those of the recent consideration of a dilute Bose gas, make it possible to conclude that the pairwise interaction in a quantum gas has an essential and nontrivial effect on the kinetic energy, which is not the case for a classical manyparticle system.   
Language 



English
 
Source (journal) 



Physical review : A : atomic, molecular and optical physics.  Lancaster, Pa, 1990  2015  
Publication 



Lancaster, Pa : 2004
 
ISSN 



10941622 [online]
10502947 [print]
 
Volume/pages 



70:6(2004), p. 113
 
Article Reference 



063618
 
ISI 



000226418900116
 
Medium 



Eonly publicatie
 
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